Imagens das páginas

called "

“noble savages” as jealous of intrusion as in 1873, was finished, when they went back to graze; but as and cannot their antipathy to strange faces and soon as it struck up again, they put their heads over cloth coats be overcome, either by law, stratagem, the wall again. This went on till the band left, or civility ? Perhaps some brother of the net and after which they ate little all day, and were pin can throw light on the present condition of continually lowing.-L. W. this queer “preserve."-W.H.G.

FROGS AND GOLDFISH.-A friend of mine had a n FOSSILS NEAR WATFORD.-In the very useful small pond, in which be kept goldfish. These began "Saturday Half-Holiday Guide” for 1873,mention is to die very fast. He could not account for it at all : made of a cbalk-pit in Berry Wood, near Aldenham, till at last one night he went very quietly up to the one mile and a half from Watford, abounding in pond, and to his surprise saw four frogs, each well-preserved fossils of various kinds. May I ask swimming on the back of a goldfish, holding on by if this pit is still available to the geological ex their webbed feet; the fish were swimming with cursionist?-W.H. G.

their backs out of the water, and seemed as if they

could not descend with their riders. In time all WHITE BEES, &c.-A subscriber would be glad the fish died. Can it be accounted for by the frogs if any of your correspondents can inform her what on them ?-L, W. are the “ White Bees," which bees occasionally turn out of their hives, and why they put them out. The

SPARROWS AND PEAS.-Sparrows (Passer domesonly mention she finds made of them in Pettigrew's

ticus and P. montanus) do an unknown armount of Handy-book of Bees” is, that the bees tarn

harm in the kitchen garden, by eating the young them out when“ on the border-land of starvation."

shoots of beet, peas, and beans. My peas were She has only begun to keep bees this year, and kept back a fortnight, and the beet is quite ruined during the wet weather had four white bees put

this year. I was told soot would stop them; so I out, and later, two, very small ones. She has fed got some, and after I had sown my peas, I covered the bees constantly during wet weather, and on

them over with it, and they have not been touched. rainy days.-Also, can any contributor to the

What can there be in soot that keeps them off ? SCIENCE-Gossip explain the formation of stones

Mocoes,” found at Aberystwyth, and

DEATH OF ROBINS.—There is a saying in North probably other places on the Welsh coast? When cut and polished, they are like pieces of sea-weed

Lincolnshire that all the two-year-old robins floating in the stone, which is transparent, as if

(Erythaca rubecula) kill all the three-year-old birds water and weed had both been suddenly changed to

in autumn. Is there any truth in this or not? I stone. The weed in many cases is very perfect, and

have watched them for some years, and certainly there are several different kinds. Are they petri.

they are a quarrelsome set, but I have not found

that they kill each other. There is also a belief factiors, or fossils ? And are they of modern or ancient formation? I have been unable to find any

that it is unlucky to take robins; so, when all other

birds' nests are taken, it is watched with reverent description or account of them in the books I have

care.-L.W. been able to refer to.-E. 4. K. POPLAR HAWK CATERPILLARS. I have reared a

CRABS OUT OF WATER.-On Tuesday, Septem

ber 7, the gardener, in procuring a can of seawater considerable number of these caterpillars from the

for the aquarium, captured a few small shore crabs, egg upwards, but bave never experienced what

known here as “king crabs” (Carcinus mcenas), one your correspondent states in the September number of this magazine. When first hatched they were

or two of which escaped from the can after it was

brought into the garden. On the 9th one of the very delicate indeed, generally half their number dying; but after they once got over their first moult

crabs was found walking about on the stone steps, they were as voracious and healthy as could be

apparently none the worse for forty-eight hours' wished. The young caterpillars should be kept in

absence from the ocean. A trifling shower on the

morning of the 8th might have supplied it with a a small box, until they are large enough to be little moisture which would probably be beneficial, removed into the breeding-cage, as this prevents though immersion in fresh water is fatal to marine their wandering too far away from their food, which

crustacea.-G. Guyon. is an important point when they are very young. Many people seem to think that young caterpillars FISH-CANS.—“A self-air-acting fish-can” is rerequire young and tender leaves; this is true enough, ferred to by A. G. R. Sclater, in his notes on and holds well with many species, but certainly not “Goldfish Breeding,” in September SCIENCE-GOSSIP. those feeding, on poplar, as the young leaves and Wbat sort of can is this,-can be describe the shoots are always more or less covered with a arrangement ?-G. S. gummy substance, which seems to answer the same purpose as birdlime, for no sooner do the young

COMMUNICATIONS RECEIVED UP TO STR ULT. FROM:caterpillars attempt to walk over them than they

A. P.-E. T. E.-W. P.-W. K, M.- Dr. R. M. B.-J. E. L.stick fast, and soon die. I have lost numbers in T. G. P. Y.-G. G.-W. H.-P.K.-E. L.-A. B.-R. C. B.this way.' I need hardly say that they should be J. C.-T. J. B.-S. A. 8.-J. B.-J. F. R.-H. W.L.-C.P.H. handled as little as possible, and not kept in a very

-E A. K.-W., H. G.-J. H. M.-L. W.-C. 0. G. N.

G. S.-J. A. jun.-Dr. G. B.-S. J. B.-W. H. H.-W.T.B.warm room.-C. P. Hall, Woolwich.

F.J. A.-E. W.A.-Dr. C. R. A.-B. B.-E. A. B.-W.G.P.

-W.J. H.-J. P. W.-W. K. G.-W. H. G.-B. B. W.OXEN AND MUSIC.--I have often noticed the W. R. J.-E. T. S.-F. E. F.-W. T.-C. D.-W. H. H.power music has over oxen. The other day we had

-F. E. F.-H, E. W.-P. S. S.-H. G. G.-C. L.-J. G.à brass band playing in our garden. In a field

T. R.-J. G. R. P.-8. A. B.-G. C. D-J. B.-J. R. adjoining were four Scotch oxen; when the band W. H. C.--H. S. F.-C.D.-F. H. W.-C. D. W.-F. W. M.struck up-they were at the far end of this, a nine R. D.-W. A, L.-E. J. L.-D. M.-T. H.-R. H. P.-E. C.acre field, quite out of sight, the field being very

T. B. W.-J. I.-C.T. F. N.-W.F.-C. A. 0.-E. E-C. A.

-G. H. K.-J. R. 8. 0.-T. C. 0.-W. R. H.-M. P. E,uneven-they set off full trot to the garden wall,

E, M.--E, L.-J. S, H.-E. D. B. M.-W.W.C.L.J.-W.C. put their necks over, and remained so till the tuné

W. T. S.-W. E.-F. H. A.-C. H. M.-F.M.-J. C.-W.J.L.

&c. &c.


To CORRESPONDENTS AND EXCHANGERS.-As we now publish SCIENCE-Gossip at least a week earlier than heretofore, we cannot possibly insert in the following number any communications which reach us later than the sth of each month.

FLOWERING Rush.-The correspondent who wanted this plant in exchange for Sundews, &c., forgot to give his name and address.

W. H. HATCHER.– No specimen of green flower was enclosed in your note. It must have been omitted in sealing.

C. W. H.-One of the best Elementary books on Zoology is Prof. Nicholson's, published by Blackwood, at 25. 6d.

W. L. W. E. (Winchester).-Your plant is Rubus odoratus.

THE WANDERER.-You are correct in supposing the species to be insectivorous: it is the Drosera binata, closely allied to the elegant little Sundews of onr bogs.

H. F. E. W. (West Meon).-The shrubby plant, with spines without flowers or fruit, is indeterminable. Perhaps you would look out for flowers next season. The common, or local names of plants or trees, are never very reliable, they vary much with locality. We shall at all times be most happy to aid you; you cannot send us too many queries.

C. T. (Bournemouth).-It is not M. altissima, but, as you imagine, the true Melilotus alba.

W. A. LAW.-Your specimen is a Myriapod (Geophilus electricus), well known for leaving a phosphorescent trail on damp hedge-banks, &c. It is not an uncommon insect.

W. Farrow is desirous of obtaining specimens of the Grass of Parnassus. Will some of our readers send a specimen ?

S. J. BARNES.-You can obtain, mounted and named, British Sea-weeds either separate or as a perfect collection, by applying to 192, Piccadilly.

D. 0. N.-One of the handiest books we know on the subject is William Swainson's " Treatise on Taxidermy."

T. J. B.-We would advise you to get “Wild Flowers worth Notice," by Mrs. Lankester, published by R. Hardwicke, 192, Piccadilly.

E. M. GREENFIELD.-You can gain what information you require by applying to Van Voorst, the publisher of the books you mention.

E. W. ANDREWS.-The objects enclosed were the eggcapsules of a species of Natica.

Eggs of Teal, Heron, Quail, Kestrel, Sparrow-hawk, Carrion Crow, Coot, Stonechat, Lesser Redpole, and others, for good Lepidoptera.-W. Howard Campbell, Ballynagard House, Londonderry, Ireland.

UNMOUNTED Microscopic Material for other, or for Slides. Lists exchanged.-R. H. Philip, 28, Prospect-street, Hall.

WANTED to purchase for_herbarium, rare European and other Saxifrages.- Address, T. H., Highfield, Sydenhain-hill, London,

CORRESPONDENTS wanted abroad to exchange British Lepidoptera for those of foreign countries. I would also exchange British Lepidoptera for Birds' Eggs.-W. Watkins, 21, Caves-terrace, Shepherd's-bush, W.

Colchicum in flower, Linaria spuria, and Elatine, Eriocaulon septangulare, Scirpus pauciflorus, for other plants.-G. C. Druce, Northampton.

Helianthemum guttaturn (Mill), from Boffin Island, co. Mayo; also Menziesia polifolia (Juss.), from Connemara, for rare British Plants.- Richard M. Barrington, LL.D., Fassaroe, Bray, co. Wicklow.

WANTED, Nos. 1496, 870, 878, 1266, 1604b, 1616b, 1623b, 1634b, c, 1636, 1649, 1653 ; offered : 158, 235, 236, 237, 239, 253, 304, 305b, 306b, 328, 330, 335, 388, 611, 749, 8350, 887, 923, 1004, 1344, 1345, 1375, 1376, 1476, 1483, 7th edition, London Catalogue.-James Cunpack, Helston, Cornwall.

CUBA, Jamaica, and South Sea Shells, Tropical Seeds, Minerals, Adriatic Seaweeds named, for Micro. Slides.-N., 18, Elgin-road, St. Peter's-park, W.

WANTED, Helix virgata or rufescens (from localities north of Leeds), Pupa secale, Anglica or Muscorum; offered: Clausilia biplicata, Zonites nitidus, Assiminea Grayana.W. H, Hatcher, Belmont Works, Battersea, London.

WANTED, Slides, well mounted, illustrating Physiology and Anatomy; will give two good Slides for one good Slide show. ing sweat-ducts and glands plainly. Great many Slides to exchange.-W. Tylar, 105, Well-street, Birmingham.

MAHOGANY, cork-lined, air-tight case, with over 200 speci. mens of British and Foreign Beetles; also a similar case with a few Orthoptera and Lepidoptera, for Microscopic or other articles.-W.G., Gordon-street, Naim, N.B.

WANTED two or three dozen each of the larger British Land and Freshwater Snails, H. aspersa, H. pomatia, L. stagnalis, &c., alive. First-class Micro. Slides cr Cash.C. L. Jackson, Hesketh, near Southport.

Linnea glabra offered for Helix lamillata, H. redelata, H. obvoluta, Bulimus montanus, Clausilia Rolphii, C. laminata, C. biplicata, Cyclostoma eleganı, &c.—Edward Collier, 6, Short-street, Tib-street, Manchester.

WANTED, Healthy Plants of Flowering Rush (Butomus), Arrowhead (Sagittaria), Water Soldier (Stratiotes). Good Plants of Sundew, Drosera rotundifolia (see Darwin's “ Insectivorous Plants") will be given. - Miss E. De B. Meyrick, Downshire Lodge, Blessington, co. Wicklow.

Hyas araneus, Corystes Cussipelaunus, and other Crabs for Lithodes maia, Nephrops Norvegicus, or otber Dorthern species. Lists exchanged.-Thos. Russell, 48, Esser.street, Strand, W.C.

SMITH's best {th Objective, with screw adjasting collar, and Kirby & Spence's “Entomology," 4 vols., original edition, with MS. notes, by Mr. Spence, for a good fth or ith. A little cash given as well, if required.-J. S. Harrison, 48, Lowgate, Holl.

CORNISH PLANTS :-125, 139, 854, 944, 946, 947, 948, 956, 981, 1052, 1389, 1401, 1485, 1486, 1508, 1651, London Catalogue, 7th edition.-Wm. Curnow, Pembroke Cottage, Newlyn Cliff, Penzance.

DUPLICATES of H. velleda, L. complanula, E. jacobea, C. dominula, L. chrysorrhæa, L. auriflua, L. dispar, W. samburate, M. margaritaria, D. acersata, É. piniaria, 1. ocellata, &c. &c. Desiderata : Lepidoptera, Birds' Eggs, or Mollusca.W. K. Mann, Granby House, Granby Hill, Clifton, Bristol.

EXCHANGES. Eggs of Golden Plover, Ring Ouzel, Lesser Redpole, Mountain Linnet, Kingfisher, for other good Eggs.-Address, Jas. Iagleby, Eavestone, near Ripon.

WANTED, Parasites, mounted or unmounted; will give other Material unmounted.-F. E. Fletcher, Eastnor House, South Norwood.

Mentha rotundifolia, for any of the following Labiatæ :945, 948, 949, 954, 956, 958, 965, 966, 971, 985.- Rev. F. H. Amold, Fishbourne, Chichester.

For large Male Antenna of Bombyx Yama-mai, send a stamped directed envelope to W. H. Gomm, Somerton, Taunton.

MOUNTED Tentacle of Drosera rotundifolia, for other well-mounted Slide.-J. B., 224, West George-street, Glasgow.

WANTED, Parasites, mounted or unmounted, for other Material unmounted, or Coloured Varnish for ringing.-F. E. Fletcher, Eastnor House, South Norwood.

Maloa borealis, for Nos. 1302, 1487, or other rare plants.C. A. Oakeshott, 8, St. Andrew's-square, Hastings.

FOR Sheep Tick, Melophagus ovinus, mounted in balsam, send any good Slide to A. Haward, 1, Shirley Villas, Addiscombe, Croydon.

Rosa Wilsoni et sylvestris (Menai Bridge), for other Roses, &c.-H. S. Fisher, 1, Gladstone-road, Edge. hill, Liverpool.

Ecos of Heron, Grouse, Guillemot, Sandpiper, Sandwich Tern, Black-headed Gull, and Green Woodpecker, for other good specimens.-Alfred Bindon, 22, Argyll-street, London, W.

Eggs of Lesser B. B. Gull, Pratincole, Sandwich Tern, Kentish Plover, and Fieldfare, for other rare Eggs.-C. Dixon, 60, Albert-road, Heeley, near Sheffield.

OFFERED, good specimens of Sphinx Convolvuli for Sphinx Pinastri, or specimens of the Deilephilæ.--Rev. F. H. Wood, 2, Clarence Villas, Finsbury-park, London.

A Few Beetles (continental species), mounted and named, offered for odd Nos. of GOSSIP, for 1874.-G., 15, Thornhillroad, N.

A Few specimens of Lepidoptera, Shells, Birds' Eggs, and Minerals.-G. T. F. Napier, Alderley Edge, Cheshire.

For well-mounted section of Ivory, send really good Slide (number limited) to J. Green, March.

Hair of Opossum (upmounted), for any object of interest, also Foreign Shells for others.-F. W. M.. 40, Bengal-street, Bradford.

BOOKS, &c. RECEIVED. “ Climate and Time." By James Croll. London: Daldy, Isbister, & Co.

" The Dawn of Life." By Principal Dawson. London: Hodder & Stoughton.

"Introductory Zoology." By Prof. Nicholson, 2nd edition. London: W. Blackwood & Son.

“ Zoology for Students.” By D. Carter Blake. London: Daldy, Isbister, & Co.

“Report of Botanical Localists' Record Club." “How to Use the Microscope." By John Phin. New York. "Monthly Microscopical Journal.” October. “ Popular Science Review." “ Canadian Entomologist." “ American Naturalist." August, “Land and Water." October. “ Les Mondes.” October. “Monthly Journal of Education." October. “Ben Brierley's Journal,"





HIS singular, but be had every day in the year. The juice of the handsome vege- artichoke, pressed out before it blossomed, was table, is nearly used by the ancients to restore the hair of the head, allied to the car. even when it was quite bald. They also ate the duus, or thistle, root of this plant (as well as that of the thistle) and is a native sodden with water, to enable them to drink to of some of the excess, as they excited a desire for liquor. Colu

parts mella notices the same quality in the artichoke, but of the temperate zone; it is intimates that it injures the voice,also considered to be indige

“Let the prickly artichoke nous to the countries which Be planted, which to Bacchus, when he drinks bound the Mediterranean, as

Is grateful; not to Phoebus, when he sings." well as the islands which are

Pliny tells us that these thistles are grown in two situated in that sea. It is different ways, from plants set in the autumn, and almost impossible to trace when from seed sown before the Nones of March (7th), this vegetable was first used in which case they are transplanted before the Ides as food, but Dioscorides men

of November (13th), or, where the site is a cold one, tions it more than half a cen.

about the time when the west wind prevails. They tury before the Christian era. are sometimes even manured, and, if such is the

Two Greek authors, of an early will of Heaven, grow all the better for it." date, recommended mothers desirous of having male Bechmann, in his “History

of Inventions,” made children to partake freely of this vegetable. Both very laborious researches to ascertain the positive Greeks and Romans appear to have procured this antiquity of the artichoke, and these discussions are plant from the coast of Africa, about Carthage, and both curious and interesting. We find the first also from Sicily. This vegetable is said by Pliny mention of this vegetable, in more modern times, to have been more esteemed and to have obtained about the fifteenth century, when it was introduced a higher price than any other garden herb. He into Italy from the Levant, and considered as a new was ashamed to rank it among the choice plants of species of food. In 1466 one of the Strozzi family the garden, being, in fact, no other than a thistle. brought the first artichokes from Florence to He states that the thistles about Carthage and Naples. A commentator of Dioscorides, HermoCorduba especially, cost the Romans annually leus Barbarus, who died in 1494, relates that this 6,000,000 sesterces, about £30,000 sterling; and vegetable was first seen in the Venice garden in concludes by censuring the vanity and prodigality 1473, at which time it was very scarce. It was of his countrymen in serving up such things at table introduced into France at the beginning of the sixas the very asses and other beasts refuse, for fear of teenth century; and not many years after, during pricking their lips. We are also informed by the the reign of Henry VIII., was first transplanted same author that the commoners of Rome were into our gardens. In the Privy Purse expenses of probibited by an arbitrary law from eating this vege this king we find several entries regarding artitable. The Romans used to preserve the artichoke chokes. Thus,—"Paied to a servant of maister in honey and vinegar, and season it with the root Tresorer in rewarde for bringing Archecokks to the of laserwort (Laserpitium glabrum) and cumin king's grace to Yorke-place, iijs. iiijd." A treatise, (Cuminum cyminum), by which means they were to written in the reign of Mary, on the “best settynge

No. 132.

[ocr errors]

and keepynge of artichokes," is still preserved in a maritime plant, or at least one which thrives best the Harleian Library, of which it forms the 645th on soils where there is a mixture of saline or alkanumber,

live matter. In the time of John Evelyn, 1699, the Gerard has left us correct representations of both island of Jersey was famous for its artichokes, the French and the Globe varieties, but makes no on account of the seaweed used in manuring the mention of their country or their introduction; we land; and it is said that in the present day this may therefore conclude that they were become vegetable is ccessfully cultivated in the Orkney common in 1596. By reason of the great moisture Islands from the same cause. of our climate, and the attention which was paid to Medicinally, the stalks are considered aperient its cultivation, the artichoke soon became so much and diuretic; the leaves in their natural state. improved in size and flavour that the Italians sent boiled in white wine whey, are thought beneficial in for plants from England, deeming them to be of the case of jaundice; and when cut into pieces and another kind; but they soon returned to their steeped in sherry wine, are an excellent antibilious natural size when restored to that country. In its medicine. wild state the plant is said to be taller, more downy The generic name Cynara is said to be derived and spinous, than it appears in our kitchen-gardens. from the word cinis, because, according to Cola. It is cultivated in almost every part of Europe, but mella, the land for artichokes should be manured in England it is grown rather as a luxury than with ashes; and Gerard says the same thing. a profitable succulent. On account of the great | Parkinson says it is so called from the colour of its size of its roots, and of its penetrating the soil leaves. Heathen mythology informs us that Cynara so deep, it withstands the dry and hot summers was a young and beautiful girl who had the misforabout Paris, where they are most extensively culti tune to displease one of the gods, who instantly vated and most abundantly used. Artichokes are metamorphosed her into an artichoke. (Ruell, i. a favourite dish at a French breakfast; sometimes 20.) Respecting the origin of the word artichoke, they are eaten uncooked in a young state as a salad. various conjectures have been formed. It has been The young heads, when about 2 in. in diameter, make by some authors derived from the Greek word excellent pickle. In England they are generally coccalon, which signifies a fir-cone, with the Arabic boiled, and the scales of the calyx are then pluckedal prefixed; this, again, has been denied, and off one by one, the lower part of them dipped in the word drawn from the Arabic name, harraf, or melted butter, and the fleshy substance sucked harchiaf. from the rest. But there is generally so little to be The artichoke has been introduced into the obtained, as almost to justify the observation of a Pampas of South America, and has spread over a raw country servant, who, having waited at supper large tract of country in such abundance as to form when artichokes made one of the dishes, was eager impenetrable masses when in flower. (Vide Oliver, on his return to the kitchen to taste a kind of food “Lesson in Elementary Botany.") he had never seen before, but to his great disap

HAMPDEN G. GLASSPOOLE. pointment, finding little more than a horny substance which equally defied his tongue and his teeth, declared with great naïveté that gentlefolk THE RESTING SPORES OF THE POTATO seemed to bim to have strange fancies, for, as far as

FUNGUS (continued). he could discover, one leaf would do as well to lick

BY WORTHINGTON G. SMITH, F.L.S. up butter as a thousand. It was fortunate for him that he did not encounter what is emphatically VINCE this subject has been made public, Mr. styled, the “choke,” from not an ill-founded persua. sion that any unlucky wight who should happen to of Dr. Farlow's paper on the Potato Rot, extracted get it into his throat would certainly be choked. from the “Bulletin of the Bussy Institution," This consists of the unopened florets and bristles part iv., a paper 1 had not previously seen. As which stand upon the receptacle of the compound some of Dr. Farlow's practical observations seem flower, and must be carefully cleared away before to have a direct bearing on some of the points the epicure can arrive at the receptacle itself, the raised by me, I will conclude by extracting one or bottom, as we call it, or le cul, as it is more elegantly two sentences :-“The disease is first recognized termed by our polished and refined neighbours on by brown spots on the leaves” (p. 320). "If we the other side of the Channel, which is undeniably examine any potato-plant affected by the rot, even the most plentiful as well as the most delicate part before any spots have appeared on the leaves, we of the viand; and in France it is esteemed a branch shall always find these threads in the leaves, stem of good housewifery to preserve this part to the use and, in fact, nearly the whole plant” (p. 322). of the family during the winter. (Rees's “Cyclo- "The Peronospora is much more easily affected by pædia.")

moisture than the potato-plant itself.” “Suppose The artichoke, like the asparagus, is naturally the temperature to keep equally warm, and the

[ocr errors]

“ When

atmosphere to become very damp, then the absorb confound them with corroded cells, granules of ing power of the mycelium is very much increased, starch injured by the disease, or foreign bodies. while the assimilating power of the leaf-cells is At 2 is shown a semi-mature resting spore with little altered. Thus it happens that a sudden change pollinodium attached, accidentally half washed out from dry weather to moist will cause the mycelium of its coating of cellulose by maceration in water. to increase so very much beyond the power of the I may say, as an addendum, that to me there is a potato-plant to support it, that in the struggle for marked analogy in size and habit on the one hand existence the latter blackens and dies.”

between the oogonia and the vesicles which contain the disease has arrived at a certain point, viz. just the zoospores, and on the other hand between the about the time of the appearance of the spots on simple spores and the antheridia. I consider that the leaves, these mycelial threads make their way 'the oogonia and antheridia are merely the interinto the air” (p. 323).

cellular condition of the vesicles which contain the I give in conclusion an illustration of the perfectly zoospores and conidia, which latter are the aërial mature resting spore of Peronospora infestans, as state of the former. seen imbedded in the substance of the potato-leaf. The facts which point in the direction just indiThese resting spores, which carry on the winter life cated are these : sometimes there is no differentiaof the fungus, are not restricted to the leaves, for I tion in the contents of the vesicles, but the plasma find them sparingly in both haulm and tuber, al is discharged in one mass and not in the zoospore though I have at present seen the best specimens in condition; the vesicle then resembles the oogonium. the leaves. The engraving given herewith (fig. 164) At other times the oogonium shows a distinct difshows a transverse section through a black spot of ferentiation in its contents, and matures from one one of the leaves from Chiswick, and the resting to three resting spores, which to me shows an spore is seen at a, nestling in amongst the cells of approach to the condition of the vesicle which the loaf. An antheridium, B, and two oogonia usually gives birth to the zoospores. -See also the (c, c), from which such resting spores arise, may Gardener's Chronicle, July 17 and 24, from which be seen in the cut, and the old common form of the the above plates have been taken. fungus will be noticed breaking through a hair on Since the above observations were printed, the the upper surface of the leaf, which is a very un following facts have been observed by me, and recommon occurrence. The situation of the resting corded in the Gardener's Chronicle for July 31. spores can generally be ascertained on the leaves 1. Some plants sent to the Royal Horticultural by noticing the slightly thickened and very dark Society by Mr. Dean, on July 21, were covered with spots, for the bodies are commonly in these spots. the Peronospora far beyond anything I had ever It is, however, an extremely difficult matter either seen before. The haulm, the leaves (on both sides to get them out, or, indeed, to see them when im- alike), and the berries were covered. Some of these bedded, for, when mature, they are black-brown in plants, after being placed on a garden bed, and colour, and only a little larger in size than the leaf covered with leaves (to keep them moist), were the cells. These leaf-cells are also intense brown-black next day one white mass with the Peronospora. in colour, from contact with the hurtful mycelium, 2. The potato fungus (as commonly seen) bears a and almost as hard as wood. The best way to see far larger number of simple spores than inflated the resting spores is to macerate the leaves for

vesicles containing the zoospores or swarm-spores, several days in water, and then set them free by but in Mr. Dean's plants the fungus produced crushing the spot between two slips of glass. The zoospores almost exclusively, and in the greatest presence of the fungus in the leaf makes the cells abundance. As the zoospore is a higher developvery thick and woody as well as black, so that in ment of the plant than the simple spore, this latter crushing the leaf-cells the resting spore is not un observation points to the unusually robust health of commonly crushed at the same time. With care, the fungus this season. however, they can be got at, when they will be

3. On suspending the infected leaves over a glass seen, as at D, covered with warts or coarse reticu of water for from twelve to seventy-two hours, the lations, and beautifully regular and perfect in out. swarm-spores fell in abundance (either free or in line : when Iyoung they are of a pure warm sienna the vesicle) on to the water, and there germinated. colour, and when perfectly mature, brown-black No single drop of the water could be taken up for and shining. They are spherical or slightly egg examination without meeting with the germinating shaped, and measure on an average about one spores, the threads radiating over the water in every thousandth of an inch in diameter. I consider it direction, evidently in quite a congenial element. worthy of special note that these resting spores are It brought the following fact to light, which is of almost exactly the same in size, conformation, and importance : some of the vesicles which usually

with Peronospora arenaria, Berk., an allied discharge the zoospores discharged instead a thick species found parasitic on Arenaria trinervis. In mass of mycelium; and this cord, when it had prolooking for these bodies care must be taken not to ceeded a considerable distance over the water, there

« AnteriorContinuar »