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straight spine is imbedded in the muscular tissues at the back of the head. The structure of the paired fins, so far as can be ascertained, is singular, and there is a long dorsal fin behind the spine, but the caudal is imperfectly known. The skin appears to have been almost destitute of shagreen, and hence traces of the internal skeleton are well shown; there is evidence of the notochord being persistent, but neural and hæmal arches, with interspinous elements for the support of the dorsal fin, are distinctly visible.

known by Sir Richard Owen in his “Odontography," in 1840. The crown of the tooth is somewhat petalshaped-a peculiarity suggesting its name--and is fixed upon a remarkably long root; the cutting edge is slightly denticulated, and a number of transverse folds of enamel usually appear at the base. It is essentially a laniary tooth, and no part can have been used for grinding or crushing ; but the mode of arrangement of the dentition in the mouth, and the number of its components, can only be inferred from what is known of allied forms, no very perfect

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examples of jaws of Petalodus itself having hitherto PETALODONTIDÆ.

been met with. It occurs abundantly in the Lower Like the group just considered, the Petalodonts Carboniferous, and specimens have even been reconstitute an extinct family, ranging only through a corded from the Coal Measures, but, as will presently limited space of geological time; numerous genera, be shown, the identification of the latter must be or so-called genera, are known to occur in strata of regarded as doubtful. Lower Carboniferous to Upper Permian age, but

(To be continued.) none appear to have been discovered in deposits of later date. These fishes were evidently destitute of spines, and so are represented as fossils merely by On June 9th a statue of Mr. Darwin, executed by teeth, shagreen, and occasional fragments of cartilage ;

Mr. Boehm, R.A., was unveiled in the British but we are fortunate in possessing important informa Museum of Natural History, South Kensington, in tion regarding the arrangement of the dentition in at presence of the Prince of Wales and a large assembly. least two of the forms, and these particulars afford | Professor Huxley, as Chairman of the Memorial valuable aid towards determining the natural affinities Committee, made over the statue to the Prince of of the group.

Wales, who represented the Trustees of the Britis The type-genus is Petalodus (fig. 111), first made | Museum.

rape and toothwort, hence called root-parasites, and PARASITICAL FLOWERING PLANTS. | those that live on the stem or branches as the mistleBy A. D. WEBSTER.

toe and dodder.

The genus Orobanche comprises some half-a-dozen THIS curious and interesting class of plants has species, most of which are difficult to recognise, and

1 but few British representatives, and these, have given a more than ordinary amount of trouble with perhaps one exception, by no means ornamental, in classification. They are fleshy herbs, with tuberous which will, to a great extent, account for the very

roots, and never truly green, but generally of a meagre information we at present possess regarding brown or russet colour. They are also destitute of the various species of which the family is composed. leaves, but covered instead with small, brown or

reddish scales.

These plants present the remarkable peculiarity that each species is generally confined to or lives on the same species of plants, thus the Orobanche major feeds upon furze and broom ; 0. rubra upon thyme ; 0. ramosa on hemp and lucerne ; 0. minor on red clover, turf, &c.; 0. elatior on various species of composite, as centaury and milfoil; and O. cærulea on Achillea millefolium.

The greater broom-rape (0. major) is, as its name denotes, our largest native species. Here I have found this plant in considerable quantity, but, strange to say, always parasitic on furze and never on broom as the popular name would lead one to suppose. In most botanical works it is also stated to be found in greatest quantity on broom, less so on furze.

This cannot be attributed to the want or absence of broom here, for in several cases where I have found the broom-rape growing in abundance, there were also in close proximity numberless plants of the broom, so that had a preference been given, as is generally believed, there is no doubt it would have been found on the latter plant, especially under such favourable circumstances. I have also frequently noticed that this broom-rape seems to prefer living on such plants as grow in a warm, dry, usually sandy soil and sheltered situation, as on the more exposed parts of the ground, although furze may be growing in quantity, the broom-rape gradually disappears, whereas on the southern and consequently warmer side it is found in abundance. The root is tuberous and composed of a number of lanceolate, fleshy scales, somewhat similar in appearance to those of the lily, and so closely packed together at the centre that when cut across with a sharp knife the root appears quite solid. The scales on the outer

portion of the root are, however, less firmly packed, Fig. 111.–Orobanche rapum. Broom-rape.

and the points slightly protruding. When bursting

through the ground the shoot in size, shape, and Among British parasitical plants are the follow. appearance very closely resembles that of our garden ing genera : the dodder (Cuscuta); broom-rape asparagus, even the peculiar purplish hue, so char(Orobanche) ; toothwort (Lathræa); and mistletoe acteristic of that plant when in a young state, is not (Viscum album) ; these again being subdivided into wanting in the orobanche. The reproduction of about a dozen species, the following being a short this plant, which is both marvellous and interesting, description of each, with original notes jotted down is affected either by seed or increase of the root. In as opportunities offered. These parasites may be | the latter case the new root or tuber, as in our divided into two kinds, viz. : those that attach them- | common Orchis, is produced alongside that of the selves to the roots of different plants, as the broom- | one supporting the present plant, and inwards


towards the main stem of the gorse. The root is, | as a memento of the plant. The average size in this however, capable of producing more than one new district when growing under favourable circumstances tuber at the same time or during the same season, as is, however, from two to two-and-a-half feet in I have frequently found after careful examinations of | height. old plants that there were two and in some cases The lesser broom-rape (O, minor), though smaller three new tubers formed, and ready for advancing in all its parts, very nearly approaches in general into active growth in spring. They are usually structure the former species, indeed it is questionable attached to the roots of the gorse at a depth of from if these two species are specifically distinct, as the four to six inches, and never, that I have seen, above different plants on which the orobanche grows seem ground level.

to alter the nature of the so-called species in a The propagation by seed is a very slow process, remarkable degree. As the name indicates, this these usually requiring three and in not a few cases plant is usually of smaller growth and more slender four years to produce flowering plants. The plants than 0. major, and with more or less of a blue tinge never appear above ground until of a flowering size, in the flower, but this is by no means constant, as which will readily account for the absence of young forms with pale yellow and deep blue flowers are not specimens-a fact which has frequently been noted uncommon. This species seems to be by no means and commented upon by accurate observers. As all particular as to the plant on which it grows, having the specimens examined were, as above stated, been found somewhat plentiful on our common ivy, growing on the gorse roots at a depth of from four to clover, the Eryngium, &c., and varying much six inches, I have often been puzzled to satisfactorily according to the plant, as well as situation, in which account for how the seeds penetrate to such a depth. it is found—this having no doubt given rise to the The only probable explanation, and one that will also several varieties into which the plant has been account for the greater abundance of the plant in divided; but the differences between these varieties, gravelly porous ground, is that the seeds, being very or rather forms, are so minute and inconstant as to minute, are readily washed downwards by the heavy be deemed unworthy of separate remarks. It occurs rains through the loose sandy soil in which the plant sparingly in this country, and is more generally delights to grow.

found on the turf than any other plant. That this plant is parasitical, and not epiphytal, as Two other species very nearly approaching the Supposed by some. I have repeatedly proved beyond | latter are the clover-scented and red broom-rapes a doubt, for on carefully digging up the root it will

(. caryophyllacea and 0. rubra), the former be found impossible to sever it from that of the furze, | parasitic on galiums and the latter on thyme. It is and even when cut across at point of attachment | generally believed, indeed has been recorded on the both seem so perfectly united as to appear like one.

highest botanical authority, that 0. rubra is not I also think it is an error to figure this plant as it is parasitic, and that the plant is exclusively confined to in most floras with rootlets at the point of parasitical basaltic rocks, such as those of the north of Ireland attachment, as these, although I have gone to a great and east coast of Scotland. That neither of these amount of trouble in grubbing up plants to find if

statements can, however, be accepted as wholly such really was the case, I never could detect. correct, the following interesting and valuable informCertainly there are rootlets, as those of other plants ation, kindly furnished by Mr. Lindsay, curator of seem to have a particular affinity for working their the Royal Botanic Gardens, Edinburgh, only too way between the loose outer scales of the tuber of plainly shows. Mr. Lindsay says, “In reply to your this plant. The root of the furze also sends out tiny

| note regarding Orobanche rubra being parasitic, I rootlets which may readily be mistaken for those of | have to say that it is so, and think there can be but the orobanche.

little doubt that the other species are parasitic also. That part of the furze root where the attachment In the rock garden here, 0. rubra has become takes place is much enlarged, but outward from thoroughly established, self-sown plants have come that point it dies off, no doubt from the circulation up in different directions, but always on some species of the sap being averted by the parasitic growth.

of thymus, ostenest on T. serpyllum, never on any The plant flowers in May and, June, the period

other kind of plant.” I have no doubt that this plant being however, greatly extended in some specimens.

is more abundant in Britain than is generally From observations made for a number of years I supposed, but the inconspicuous appearance, and outhave every reason to believe that in a dry, warm of-the-way places in which it is usually found, as well season this plant attains to greater perfection, and as general resemblance to 0. major, have all much to remains undestroyed for a much longer period than do in accounting for the supposed rarity of O. rubra. during dull, damp weather. The largest specimen The branched broom-rape (0. ramosa) is a rare I have found measured thirty-eight inches in length, British species, being almost confined to a few of the had a stem one and a quarter inches in diameter, and southern English counties. This and the blue broombore ninety-nine flowers.

rape (0. cærulea), the former in particular, are the This gigantic specimen I have carefully preserved only members of the family having branched or divided stems, though this peculiarity is not constant | Kennedy Linaria purpurea is completely naturalised, in all the plants.

as is Polemonium in the grounds. In the Black Loch The branched broom-rape is a very distinct species, grew Potamogeton heterophyllus ; while the dry grassy being usually of a pale yellow or straw colour, and slope, cut into terrace gardens, yielded Gentiana seldom exceeding six or eight inches in height. The campestris, Aira præcox, Lysimachia nemorum, Carex branches spring almost immediately from the root, præcox, Origanum, and Orchis pyramidalis. By the and in an upright position, and are, at the point of side of the Black Loch Galium uliginosum occurred, juncture, slightly enlarged. When fresh, or in a grow and Nuphar and Nymphæa grew in its waters. As ing state, the stem is almost cylindrical, but becomes to the indigeneity of these latter it is difficult to state. angular when old, is slightly pubescent, of a dirty Between Loch Insh and Innermessan Hypericuni yellow colour, and furnished with but very few scales. humifusum, Arenaria rubra, Ornithopus, grew in It is usually found on hemp, and for this reason is plenty ; while the sandy and shingly tract of sea-board perhaps less plentiful than if hemp crops were between Intermessan and Stranraer afforded Atriplex more generally cultivated. This is an annual species, Babingtonii, Silene maritima, a most profuse growth but is readily propagated by sowing the seeds along of Armeria, Plantago maritima, Sclerochloa lobacea, with those of the hemp, to the root of which it will Honkeneya, Sagina maritima, S. nodosa (not the typisoon become attached.

cal form, nor yet the form glandulosa), Plantago coThe purple or blue broom-rape (O. cærulea) is a ronopus, Zostera marina, Polygonum Raii, Lepigonum small growing plant, rarely reaching a foot in height, salinum. In a little brook that ran into the sea near and readily distinguished from any other member of Intermessan, Ranunculus truncatus grew, and a the family by the colour of the flowers, which is of all maritime form of Fumaria Borai was frequent on shades, from pale violet to a deep purplish blue. It the shingle. A solitary specimen of Mentha alopecuis occasionally found branched, though much less roides grew near Stranraer. This day yielded nearly seldom than the former species.

50 additional species. In the Channel Islands this plant is pretty abun The fourth day was spent in first strolling up the dant, more so than in England, where it has only been

Bree-side above Newton. In the shady woods were found in Hampshire and Norfolk, and there always

gathered Solidago virga-aurea (a rare plant in Wigparasitic on Achillea millefoliuni.

ton), Pyrola minor, Luzula sylvatica and pilosa,

Sanicula, Geum rivale and intermedium, Thalictrum (To be continued.)

sp., probably Kochii, but the achenes had not formed; Rubus saxatilis, Hieracium boreale, Asperula odorata, Melica uniflora, Chrysosplenium oppositifolium, Allium

ursinum, Trollius Europaus, Mercurialis (rare in HOLIDAY RAMBLES

Wigton), and a Melampyrum, a form of pratense so THROUGH WIGTONSHIRE.

similar to sylvaticum as to be mistaken for it, the By G. Claridge Druce, F.L.S.

book description of the species contributing to the

error. This had the deep yellow flowers with open [Continued from p. 132.]

mouth of sylvaticum, but their size and spreading THE third day was by rail to Castle Kennedy, the growth were like pratense, to which plant the bracts

1 magnificent demesne of the Earl of Stair, whose and capsule brought it. It was quite different from judicious taste has made the park one of the most

the var, montanum. The non-occurrence of sylvaticum beautiful in Britain, and the collection of conifers

renders the hybrid theory untenable. * Galium boreale, so extensive and interesting as to be a great attraction the only mountain and almost the only northern to horticulturists from all parts of Britain, its plant, grew at the base of the cliff, but Wigtonshire avenue of the steel blue Pinus nobilis being an can scarcely own it as a native, since its home was especial feature : while the enormous extent of the undoubtedly the high ground of the Cairnsmore of terraces, the fine view of the White Loch, the Fleet, from which the seeds had been carried by the well-grown araucarias, all contribute to the general Cree. Between Glen Cree and Glenrazie Silene effect, and render a visit to Loch Insh a day of inflata was picked in its only locality noticed, and also great enjoyment. In the extensive piece of water | a pink-flowered form of Lychnis vespertina. Viola called the White Loch, which stretches for nearly a lutca, var. amæna, also grew here, and about mile to the west of Castle Kennedy, Lobelia Dort. Challoch a small patch of Equisetum sylvaticum. mania, Littorella, Scirpus palustris, etc. occurred. Further work for the day was prevented by my In the round pond grew Alisma ranunculoides, ankle, which had been dislocated in Forfarshire and var. 'subrepens, which possibly is the Alisma natans had been troublesome all along, at length preventing of the Botanist's Guide recorded from the Black

further walking, but about thirty additional plants Loch, but in which no trace of it could be found.

had been noticed during the morning's walk. Pilularia occurred also, with Helosciadium inun. datum, in the round pond. On the ruins of Castle | Dr.

* Since described as Melampyrum pratense, L. var. hians, The fifth day was by train to Whauphill, and then william and Clone Point Malva moschata grew in drive to Portwilliam. Along the road Trifolium great plenty ; Lycopsis arvensis occurred in cultivated medium was noticed in one place, and Sambucus nigra fields, and in the grass by the sea-shore Ranunculus occurred in the hedgerows. At Portwilliam, on the hirsutus, which I should think to be wild ; nearer the sea-shore and shingle grew in plenty Carduus tenui town in suspicious localities occurred Echium, Ana. florus, Rosa spinosissima, and the Crambe maritima cyclus radiatus, Phalaris Canariensis, and other introin great quantity, with ripe fruit, and then small ductions. patches of some vetch, which at first from the rigid | The result of the five days' work in the county was habit looked like Orobus, but nearer inspection showed | the recording of 509 species and 34 varieties, for a to be sylvatica, * very different from the type : instead detailed list of which I must refer your readers who of the large rampant plant, “ climbing and twisting in are interested in the subject to the Report of the tendrilled strength” over the bushes, with thin leaves | Botanical Record Club of the British Isles for 1883. and white flowers delicately pencilled with blue, It may be well to state that Balfour's tour in N. appeared a small compact prostrate plant, about two Uist, Harris, and the Lewis yielded 338 records. My feet across, with coriaceous, glabrous, and frequently own West Ross list contained 373; and Balfour's list glaucous leaves, rigid habit, short peduncles and | of plants seen in the Mull of Cantyre, &c., 456. pedicels, and flowers not nearly so large as type, suffused with a brownish-purple colour ; which, despite the crowded state of our synonyms, seems worth varietal distinction, at any rate if such forms as Lotus

SCIENCE-GOSSIP. crassifolius, Sarothamnus procumbens, or Genista humifusa are to be so distinguished. This probably is

Some details have lately been published about the the plant recorded from the Galloway coast by Prof.

Forth railway bridge. It has been in progress for Balfour. Glaucium luteum occurred at intervals with

two years and is expected to take five years more. Geranium Robert., Convolvulus, Soldanella, &c. In

Some of the girders have been placed upon the the sandy tracts the maritime form of Galium verum

piers, though the piers on which they rest are not yet (G. littorale) occurred, and in the shingle a prostrate

built to their full height, the mode of procedure growth of Prunus spinosa, about six inches high, was

being to raise the structure gradually by hydraulic plentiful ; then on a muddy tract where Sclerochloa

power, the masonry being at the same time built up had formed a turf grew Carex extensa in considerable

foot by foot beneath it. The metal-work is all of plenty ; later on came Salsola, and then on the sands

steel. The total length of the bridge will be over a near Monreith Bay came Eryngus maritimus, Carex are

mile and a half; the two main spans 1710 feet each, naria, Erythræa littoralis, Carlina vulgaris, Erodium

and the height of the rails above the water 150 feet. maritimum, Triticum junceum, etc. At Monreith on

The estimated cost is 61,600,000. the hillside in damp ground occurred Juncus glaucus, Samolus, Anagallis tenella, Triglochin palustre, Schæ In a pamphlet on “ The Origin and Reproduction nus nigricans (the latter singularly absent from a great of Animal and Vegetable Life on our Globe," Mr. part of the county), Helianthemum vulgare (another Thomas Spencer, F.C.S., F.R.M.S., states, among the rarity), Eupatorium cannabinum, Briza minor (rare), cor.clusions at which he has arrived, some which differ Rubus cæsius, etc. On the hill-slopes overlooking the more or less from those generally received. He besea in early spring there must have been a profuse growth lieves that he has discovered “the hitherto inscrutable of Scilla verna, here and there the dried capsules still principle by which life is imparted to matter," not, showing themselves, and the tubers could be turned up however, to the exclusion of a Creator. The long by scores with little trouble. Returning to Portwilliam sought origin of the life on our globe is to be found in and keeping on the hill-slopes, Equisetum maximum the fact that the acid-forming suboxide or magnetic was found in a curious state ; the barren æstival oxide of iron exists, accompanied by moisture, in branches bearing at the apex the fertile vernal spike, every reproductive germ, animal or vegetable, on the a form very rarely noticed in Britain. Then came surface of the globe; though the author allows astersome nice bushes of Rosa Sabini, then Senebiera wards that this wide statement is partly arrived at coronopus, and shortly before reaching Portwilliam, a by analogy. The preservation for ages of moisture in discoid of Senecio Jacobæa, of rare occurrence. Boswell the seed is due in part to the occult action of ozone, records it from Wexford and Sutherland ; and Sherard which “contains a double atom of oxygen with in Ray, Syn., 3rd edition, records : “ Jacobæa, Flore water and electricity, in combination with some nudo copiosissime nascens in sabulosis prope littus, iron.” It seems also that at least part of the warmth tribus vel quatuor millioribus a Drogheda occurrit ;" of the body is due, according to our author, to the and inspection of the Sherardian specimen showed it heat liberated, along with electricity, at the same to be identical with the Wigton plant. Between Port | time as the moisture in the air inhaled by the lungs

is decomposed. There is an air of dogmatism about * Since described as Vicia sylvatica, L., var. condensata. these statements. They are indeed said to be in no

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