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concurrent reproduction, it is one and the same organism that exerts both the power of individual multiplication and the faculty of sexual generation; whereas in the case of fertile nurse-forms, it is seldom they possess both; but if the nurse be endowed with the one, its offspring will be endowed with the other." ("The Beginning: its When and its How," pp. 242-3.) It sometimes occurs that the nurse acquires the power of sexual generation, also that the species passes through more than one nurse-form, either similar or diverse, before attaining the perfect form of the species. In the aphis is found one of the most decided examples of the fertile nurse-form (and one which it is very easy to study), the immature females standing in that relation to the perfect insect.

These fertile females, as has been said before, reproduce by internal gemmation, the bud falling into a proper receptacle in the parent's body, and being produced alive, exactly like its parent, except in size; each female producing from 50 to 100 young ones. So rapidly do they increase, that it has been calculated that from one individual there might be descended, under favourable circumstances, the enormous number of 4,000 billions in a single

summer.

Were it not for its many enemies, the increase of the aphides would be beyond all bounds; but fortunately for us its enemies are very numerous. Birds consume great numbers, but the larvæ of the Ladybird, feeding exclusively on the aphides, destroys them wholesale, extracting all the soft parts, and leaving the empty skins to testify to their enormous appetites. The larva of the beautiful lace-winged fly destroys great numbers, as does also that of the various species of Syrphida. In July, 1869, we were visited by a great plague of aphides, and all the three species I have named speedily made their appearance also in great numbers. The ladybirds swarmed in countless numbers, and immense numbers of their unsightly larvæ soon appeared. The rapidity with which these larvæ cleared the aphides from a hop-plant in my garden was truly astonishing. The clusters of curious pedunculated eggs produced by the Lace-wing fly were numerous, as were the perfect insects, than

fair treatment which it receives at the hands (or antennæ) of the ants. Linnæus calls the aphis the ant's "cow," and the use to which this sagacious little insect subjects it fully justifies the term. The aphides eject from the two tubes before mentioned as situated one on either side of the abdomen, a quantity of saccharine fluid, which is very attractive to the ants, and forms in some cases almost their only food. This fluid may be noticed overspreading the leaves of plants infested by these insects till they have a glazed appearance, and seem to have been washed with honey and water. It is commonly called "honey-dew," and was long a puzzle as to its origin. Not only do the ants consume the fluid voluntarily ejected by the aphides, but by a peculiar movement of their antennæ upon the bodies of their "cows," excite them to an increased supply. This has not inaptly been called "milking." But even this is not all. Kirby and Spence give a most wonderful account of the way in which some species of ants, particularly the yellow ant (F. flava), convey the aphides to their nests, and keep them there for the supply of their necessities. The yellow ant makes prisoners of a root-feeding species of aphis (4. radicum), and even carries off its eggs, which are tended with care and placed in situations. favourable for their early development.

I think it will be allowed that whether we consider the aphis as a marked example of the wonderful "nurse-form," as described by Steenstrup in his "Alternation of Generations," and one accessible for study to us all; or whether we confine our attention to its life-history and the singular connection between it and the ant, to which it is so serviceable, there is ample scope for observation, and that too of a character, from the delicacy and exactness required in its pursuit, which must of necessity be good training, should it even only extend to verifying the observations of others on. this interesting but generally unwelcome little creature.

HISTORY OF THE DIATOMACEÆ. (Concluded.)

which nothing can be imagined more delicate and PROFESSOR H.L. SMITH has published his se

beautiful or a greater contrast to its larva, which from its voracity has been named the aphis-lion. Another foe is a small species of Ichneumon which deposits its eggs in the body of the aphis, the larvæ feeding upon its soft parts. The brown and swollen skins of the insects thus infested may frequently be seen, and if placed by themselves in a glass-topped box, the active little ichneumons will soon burst through their prison and reveal the secret of the death of the unfortunate aphides.

There is another curious chapter in the history of the aphis which is worthy of notice. It is the un

cord instalment of his translation of the "Historical Preface of Kützing." This is for the most part a record of Kützing's own labours. In his "Synopsis Diatomearum" he separates the true Diatomaceæ, with hard and glassy shells (valves), from the softershelled forms, which he called Desmidies. This seems to have caused some complaints, of a desire on the part of the author to unduly multiply species; but he remarks that "not only all the species established by myself stood proof, but even many a form mentioned by me as a variety, was established by others as distinct species."

Ehrenberg took the trouble, in his third "Aid to the Knowledge of Larger Organisms in the direction of the smallest space,' ,"* to reduce most of the forms established by me in the Synopsis to such forms as were known to him; but later he has established the same forms as distinct species, in his larger work on the "Infusoria." (Ehrenberg did not publish his great work on the diatoms, "The Microgeologie," until some few years after Kützing had given his "Bacillarien" to the world. This work is a monument of patient but misdirected labour. The figures occupy 39 folio plates, and are far better than any previously published. The plan he adopted was to give a representation of all the forms that appeared in the field of the microscope, under a power of about 100 diameters. Grouped around the circle containing these forms were separate drawings of them, enlarged to about 300 diameters. This arrangement, although useful in some respects, was open to many objections, not the least of which was the necessarily heavy cost and large bulk of the book, for, not content with giving a large and small representation of an object, it was repeated again and again if it occurred in different deposits. F. K.)

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Kützing explains that the inferiority of his figures was owing to the indifferent microscope he used, and goes on to say that, however insufficient his instrument, he made by it his most excellent discovery, .viz., the siliceous nature of the Diatomacea, which soon led, through his friend Henri Fischer, of Pirkenhammer, near Carlsbad, to the other important discovery of the fossil deposit of these organisms. "I had already, in my Synopsis, called the substance of which these shells were composed glassy,' because I had even then suspected siliceous earth in these frustules. I communicated these to my friend Bilz, an expert equally renowned as botanist and chemist, at the same time asking him whether he would investigate chemically specimens which I would send to him. Bilz, however, declined the commission, stating

diatoms in separate watch-glasses with concentrated acids, applying muriatic, nitro-phosphoric, and fuming sulphuric acids. The colour of the internal parts became, under the first influence of the acids, beautifully green; but further investigations with the microscope had to be postponed until the following day. After a sleepless night, the exami nations were continued at the break of day, and at eight o'clock on the morning of May 8th, 1834, I had not only the full certainty of the siliceous character, but also of the iron contents of the diatoms. The diatoms which had been brought into contact with the concentrated acid had not changed otherwise than that their internal matter had disappeared."

The author afterwards tried the action of soda and a blow-pipe flame on a small mass of diatoms. The solution of these in the soda followed completely, and he obtained a perfectly transparent glass, which, on cooling, appeared of a vitriol-green colour, indicating the presence of oxide of iron. The interest of the preface may be said to conclude here; the remainder of it is taken up with acknowledgments of the kindness of various gentlemen who forwarded to him material from their own herbaria, and a complaint that Ehrenberg did not acknowledge, excepting very briefly and unsatisfactorily, his discoveries of the siliceous nature of the diatomaceous frustule, and the presence of iron in them. Kützing says "I was somewhat astonished to see in Ehrenberg's large work on Infusoria the iron of the Gallionelle mentioned as his discovery, while he does not even allude to the fact that I, in my essay sent to the Berlin Academy, mentioned iron as a general constituent of diatoms. It is easy to believe here in a ‘turpinate.”’

(Perhaps some of the readers of SCIENCE-GOSSIP may be able to explain this expression; I am unable to do so myself.) F. K.

A HALF-DAY'S PLANT-HUNTING.

that he had no practice in the chemical investiga- MY friend, Dr. M., having snatched half a day

S

tion of microscopic objects." The matter rested for a short time, until recalled to the author's mind while investigating some Characeæ. "I placed ome charæ in dilute muriatic acid, in order to remove the lime crust that was in the way of microscopic investigation. In the course of examination I found that the soft chara stems were on the outside garnished all over with diatoms, which were not at all affected by acids. Notwithstanding the 'twilight that had already commenced, I treated these

This title is somewhat obscure. The original is "Zur Erkenntniss grosser Organisation in der Richtung des kleinsten Raums." I understand it to mean an aid to the knowedge of that large number of organisms occupying the smallest space.-F. K.

from his arduous professional duties, we drove off from home at 1:30 P.M., with the intention of visiting the great chalk ridge at Boxley, and afterwards the village of Boxley at its foot, through which meanders a small clear stream of water, which issues from beneath the chalk escarpment.

In our journey through the woods we made numerous halts in order better to examine the nature of the flora. The woods in this district are grown for the sake of hop-poles, &c., and are cut down periodically at intervals of from seven to ten years. In the clearings thus produced the botanist finds at all times a rich reward for the trouble expended in hunting through them. The summer after they are felled a great and varied selection of

plants makes its appearance, including many rare and curious orchids, the Herb Paris, &c. &c.

The trees themselves, of which these low woods are composed, are well worthy of note. Among a great many others we noted Pyrus Aria, P. torminalis, P. Malus, Prunus communis, P. Cerasus, Viburnum Lantana, V. Opulus, Carpinus Betulus, Castanea vulgaris, Euonymus Europeus, Rhamnus catharticus, &c. Beneath these trees we found immense beds of woodruff, and pretty little masses of the beautiful Oxalis acetosella. Poterium sanguisorba is everywhere very abundant on the chalk. By the way, self-fertilization is somewhat carefully provided against in these plants. The flowers are in dense heads, the upper flowers being pistilliferous and the lower staminiferous. The stigmas of the upper florets are in a receptive condition a considerable time before the staminiferous florets open-indeed, when these latter open, the stigmas are withered and dried away. Thus it is rendered impossible for the florets on any given head to fertilize each other. The pollen must be brought from some other plant, or at all events from some other flower-head.

Arrived at Boxley Hill we wandered about in search of specimens, and were soon richly rewarded for our trouble. Some years ago I found Atropa Belladonna growing on the wooded hill-side, and in the hunt to find it again, which proved unsuccessful, we met with the beautiful Fly orchis (Ophrys muscifera), the unique beauty of which cannot be understood from any description; it must be seen to be appreciated. Many non-botanical friends to whom it was shown were highly delighted, and bore testimony to the correctness of its name by suddenly exclaiming, "How like a fly!" "It might be used as a bait for fly-fishing," &c. &c. Near the same place we found the lovely Cephalanthera grandiflora, the curious Aceras anthropophora, some fine specimens of Orchis maculata and 0. pyramidalis. My friend at this point began turning over large stones in an old chalk-pit, and we were greatly astonished to find beneath almost every stone a fine specimen of Blind-worm or Slow-worm (Anguis fragilis). The names of this lacertian appeared to us to be sad misnomers, for the creatures are very active when aroused, and far from being blind, they possess a pair of very sharp and extremely pretty eyes. We caught three, which were liberated after a careful examination.

In this pit we found the pretty Helleborus fœtidus, a great number of orchids, and a splendid plant of Rosa rubiginosa, which occurs in great abundance in this neighbourhood, &c. &c.

Among the plants here adorning the greensward were Hippocrepis comosa, Anthyllus vulneraria, Lotus corniculatus, Helianthemum vulgare, and Polygale vulgare; and Columbine (Aquilegia vulgare) was very abundant in the thickets. We met With

several specimens of a white variety of Herb Robert (not common, I think).

Tea was consumed in a lovely quiet lane near the wood. We preferred roughing it thus to driving into Maidstone. Here all our senses were gratified at one and the same time. The scenery is delightful, and, owing to the rugged nature of the ground, much land is incapable of cultivation, and many miles of hills are covered with plants and trees of great variety, growing in rich luxuriance. Hundreds of yew-trees stud the hill-sides, their dark sombre foliage contrasting finely with the intermingled richer greens of other trees. The barer spots are everywhere thickly dotted with juniper-bushes, which grow here in great abundance. About a hundred feet above us towered a white cliff of chalk, in which numerous jackdaws and starlings had built their nests, and with clamorous cries were busily performing their parental duties. In one part of the cliff a windhover had taken up its abode, and we were highly amused by watching the occasional concerted attacks made upon him by jackdaws, which did not seem to relish such a formidable neighbour. On an old wall we found Linum catharticum, Saxifraga tridactylites, Linaria cymbalaria, Arenaria serpyllifolia, Sagina, Lactuca muralis, Asplenium ruta muraria, several specimens of epilobium, and last, and most noteworthy of all, Meconopsis Cambrica. The finding of this last fairly astonished us, as its station is much to the west and north of us. Has it previously been recorded from this part of Kent? The small stream along the roadside was profusely ornamented with brooklime (Veronica beccabunga), Potentilla anserina, the Siums, &c. A wall, alongside which flows the stream, was covered about its base with the lovely golden saxifrage (Chrysosplenium oppositifolium).

From here we followed the course of the stream, and were rewarded by once more finding many an old floral friend, the sight of which recalled to us other days. A pleasant ride home in the cool evening air, enlivened by the richly-modulated song of the nightingale, the peculiar thrilling notes of the nightjar, and the mellow call of the cuckoo, brought our much-enjoyed afternoon to a close. New Brompton.

J. M. HEPWORTH.

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NOTES ON THE STARLING.

ALTHOUGH we have many of our small birds

protected, there are yet some for those who love to raise young birds from the nest, and perhaps one of the most beautiful is so left, for few birds are more handsome than the Starling (Sturnus vulgaris), and certainly none more deserving attention, for, added to his spotted, richly-shaded, purple and gold feathers, he has a talent which should recommend him to all lovers of the feathered tribe,—he is a good mocking-bird, and may be taught to talk and whistle several tunes by simply repeating them at feeding-time, or a few times during the day. The starlings are not migratory birds, but congregate in large flocks, when they are sometimes seen darting and floating after the manner of the swallow, feeding on the wing, rising and falling in a most pleasing way; yet with all their gambols they display much caution,-ever wary,-indeed, in some instances they are like the magpie; but when tame the whole of their ability may be turned to good account. See one at home in a hole in a tree or under the eaves of a cottage. Cunningly he selects his abode for the rearing of his young, sometimes but a few feet from your door, whence he may be seen to dart into a hole or cleft in a tree with food for its young, and we soon see the sleek, well-fledged young, peeping after the parent, and in the month of June the brood is led forth to learn to provide for themselves. Busily they may be seen in the sheep-walks, seeking food close to the feet of cattle, giving us an illustra tion of their instinctive cunning. But at this time we have not the elegant bird before mentioned-he is yet wearing his dusky feathers. In the month of July or August he begins to moult, and we shortly see those beautifully spotted feathers which transform this bird of exquisite symmetry into one of our handsome English mocking-birds. The Starling is insectivorous, very hardy, easily raised from the nest, and becomes remarkably tame. The cruel practice concerning the cutting of this bird's tongue is all nonsense; the bird will talk much sooner and better if his tongue be not cut. The nestling starlings should be fed with scalded bread, fig-dust, hard-boiled egg, and a little bruised hemp-seed, well mixed; or you may give them fig-dust and raw meat, taking care to prepare them fresh food daily. As soon as your nestlings can feed themselves, they should have a cage as large as the blackbird's cage, taking care to keep them very clean, allowing them to be plentifully supplied with water, and the cage well gravelled. CHAS. J. W. RUDD.

"SMOKING flowers with brimstone is a very good, simple, and cheap way of drying flowers, especially asters, roses, fuchsias, spireas (red flower kinds), ranunculuses, cytisuses, &c.”—Burbidge's "Domestic Floriculture."

TERATOLOGICAL NOTES.

whorl, and seemingly stuffing up the centre of the flower, and not all on the same plane, but crowded upon the central column. Petals.-The outer ones

AUGUST 1st.-Noticed to-day a fuchsia, of red-purple, the inner quite green; unguiculate, and

which the leaves were arranged in three different ways: not only on the same plant, but also on the same branch, there were leaves opposite, alternate, and in whorls of three, and on one branch two whorls of three leaves each, bearing a flowerbud from the axil of each leaf. Are we to suppose that this is caused by a non-development of internodes, or is there a better theory to account for it? (N.B.-I believe Mr. Lindley is in favour of the suppression of internodes.)

Fig. 96. Garden variety of Ranunculus Asiaticus-a, the 3 folioles of the Calyx, or Involucre; b, the coloured inner foliole, or abortive petal; c, the foot-stalk of the Flower.

May 16th.-On rich, light, sandy loam, in Church Cemetery, Nottingham, an abnormal specimen of Trifolium pratense or of T. medium (Bentham); the whole plant apparently full and healthy. Examined three heads of flowers, two of which exhibited the monstrosities.

The following is a description of one of the flowers, and may be accepted as a type of the rest :

Calyx.-In two whorls; the inner of four, the outer of nine sepals. Sepals.-Divided halfway to the base, with subulate teeth.

Corolla.-Nine oblique petals, arranged in an apparently rosaceous manner (these situated between the outer and inner whorls of the calyx), then five small, unequal, crumpled organs inside the inner

the nine outer ones incurved one over the other, like the blossom of an apple, but more crowded.

Stamens.-Eleven perfect ones cohering into a central solid column, and about six very imperfect green filaments at the top; these were all of various lengths, and scattered amongst the imperfect petals upon and around the column.

Pistil.-No trace, though the column, solid from the centre to the top, appeared looser in texture at the base.

The spikes of flowers were very fine ones. On them were counted 41, 45, and 66 flowers, the latter one having no abortive ones;-at least, none were noticed. The monstrosities were all at the base of the spikes, those flowers at the top being pretty regular, though every flower on the two heads appeared to possess more than its normal number of sepals, the average being 6-fid.

June 9th.-A lady found to-day a specimen of the red garden daisy, with one large centre flower, the involucre very loose and spreading, and having fifteen other daisies, half the size of the central one, springing from between the scales of the involucre. This is, I believe, a very good specimen of the Henand-chicken daisy.

June 23rd.-While plucking some flowers from a plant of the common blue lupine, noticed a peculiarity about the leaves. The leaves of this wellknown plant are commonly on long stalks, with a number of lanceolate leaflets arranged in a stellate manner upon the top of the stalk, and all upon the same plane. In this case, however, the leaflets appear to be arranged in two or three rows, and in a spiral almost imperceptible, excepting that they are alternate with the ones above. One of the leaves consisted of 29 such leaflets.

July 21st, 1873.-Perhaps the following is as good an illustration of the transitions between sepals and petals, &c., as could be found in the Ranunculus family. A garden variety of Ranunculus asiaticus produced, instead of a flower, one long stalk, on the top of which were three green expansions of a leaflike form, and one within, and alternate, of a bright red colour, and of remarkable shape. The best idea of their appearance may be formed by supposing the involucre of the Wood Anemone (4. nemorosa) to be formed of three sessile leaflets, one-third of an inch broad at base, and divided from halfway up into numerous divisions, like the ordinary leaves of the species. Within these, and springing from the same centre, one tripartite flattened expansion, coloured red, the two lobes entire, the other one approaching the divisions of the leaves, and coloured with green streaks up one side. The illustration may make this plainer.

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