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form, with a flat base and cutting edge all round, somewhat similar to a cast, in my possession, of one from the cave of Aurignac. All these were found either on or within two feet of the floor of the cave. They were imbedded in red earth, containing large stones, and enormous quantities of the remains of mammalia. Above the flint implements, in some places, were layers of comminuted bone and coprolites of hyæna ; and in and around these was the greatest quantity of bones. These layers indicated old floors. I continued the excavations up to the year 1866, and the list of mammals which I have determined is second only to that of Kent's Hole. It comprises cave lion, cave hyæna, wolf, fox, badger, cave bear, brown bear, grizzly bear, urus, bison, Irish elk, stag, reindeer, mammoth, horse, Rhinoceros tichorhinus, R. leptorhinus of Owen, water-rat, and lemming.
There was clear evidence that the cavern had been inhabited by hyænas, and that the animals to which the remains belonged had fallen a prey to them. The traces of old floors above the flint implements prove that they inhabited it after the departure of man. Such as this is the evidence of the coexistence of man with the Pleistocene mammals, afforded by the contents of caverns in Britain. The small proportion which those caverns that contain the traces of man bear to those in which no traces of him have been found, shows that he was small in point of numbers as compared with most of the other animals.
Out of the thirty caverns explored in Great Britain, the contents of which I have classified, four only have yielded human remains; while out of forty river-deposits containing mammalia, only three have furnished any trace of man. Had man been very abundant in those days, we might certainly have hoped to have found his implements more widely spread, and especially as they were fashioned out of a material that is almost indestructible. That, however, he formed an integral member of the post-glacial fauna of the Pleistocene, is proved by the following table, in which I have arranged in order the animals found with man in old river-beds and in caverns, and the animals from river-beds and caverns in which he has not been found. The correspondence of these four columns show that the deposits from which the animals were derived are of the same geological age. The Bos longifrons,* which has been inserted among the British fossil mammals by Professor Owen, is purposely omitted, because there is no evidence that the animal was living at the time in Great Britain :
*“Quart. Geol. Journ.," 1867, vol. xxiii. Brit. Foss. Oxen.
THE RELATION OF THE ANIMALS FOUND ASSOCIATED WITH THE
REMAINS OF MAN IN THE CAVERNS AND RIVER DEPOSITS TO
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Such as there were, the animals with which the first man was surrounded, the mammoth, the horse, and the bison were most abundant; the reindeer was far more common than the red-deer, and that again than the roe. The Tichorhine rhinoceros was more widely spread than the Leptorhine, and the hippopotamus than the wild boar. The cave lion and cave hyæna, wolf and fox, were moderately abundant, while the badger and brown bear were comparatively scarce. Among them man appears for the first time in the world's history, scantily armed, and few in numbers, and by the exercise of that intellect which separates him from the rest of the animal world, asserted himself their king. His craft proved stronger than their strength, and his cunning sharper than their claws or teeth. In his time Great Britain formed part of the continent, and the Thames flowed northwards to join the Rhine and Elbe in forming an estuary in the latitude of Berwick. The climate, also, was so severe, that glaciers descended from the mountains of Cambria, Scotland, and Wales, and the reindeer and musk-sheep could live in the lowlands. Then all these conditions passed away, the land became depressed, until Britain was insulated, and the waves of the Channel rolled over what was before the great feeding-ground of the Pleistocene herbivores, and the climate became warmer, until the arctic mammalia were obliged to retreat northwards. Coincident with this was the disappearance of the characteristic Pleistocene mammalia from the restricted area of Great Britain, and with them all traces of the first man, who spread over France and Italy,* using the same implements, and therefore possessed of the same habits, passed away.
* This occurrence of implements of the Amiens and Abbeville type associated with the remains of extinct mammalia in Italy, is proved by the discoveries of M. Louis Caselli, President of the Society of Immaculate Conception, in the gravel of Ponte Mammolo.-Correspondance de Rome, 4th May, 1867.
THE AIR-VESICLES OF BLADDERWORTS
[Ix England we have, amongst our wild flowers, three Bladderworts—Utricularia vulgaris, or Bladderwort, growing in stagnant water; U. intermedia, a rare plant; and U. minor, or lesser Bladderwort; and many of our readers will be glad to repeat the observations contained in the following paper, which is translated from the “ Archives des Sciences.”']
The genus Utricularia, or Bladderworts, comprises aquatic plants found in the stagnant water of ditches, marshes, etc. The leaves are submerged, and divided into fine threads, furnished with vesicles, or utricles (asci), to which De Candolle ascribes the following characters :
These utricles are rounded, and furnished with a species of movable operculum, or lid. In the youth of the plant, they are full of mucus heavier than water, and the plant, weighed down by them, remains at the bottom. Towards the season of flowering, the leaves secrete a gas which enters the utricle, and drives out the mucus, opening the lid for its escape. The plant is thus supplied with a quantity of air-vessels, which elevate it gradually, and cause it to float on the surface. The process of flowering takes place in the free air; and when it is finished, the leaves again secrete mucus, which replaces the air in the utricles, weigh down the plant, and cause it to descend again to the bottom of the water, where it ripens its seed in the situation in which they should be sown.*
In spite of the labours of Göppert,+ Benjamin, 1 Schleiden, Schacht, Reinsch, f there is not yet a complete agreement of botanists as to the origin and morphological signification of these aerial vesicles. Before the publication of the works cited, they were usually regarded as a modification of the parenchyma of the leaves, which follows the numerous ramifications of the veins, under the form of a narrow band, and which by dilating from time to time produced the utricles.
Schleiden, who studied the development of these little organs, saw them appear at the angles of the division of the leaf under the form of little bodies like horns (cornets), supported on short pedicels. The lower side of the horn, and the lower margin of its opening, which itself scarcely increased in size, developed themselves much more than other parts ; so that the complete utricle formed a small rounded body, laterally compressed, prolonging itself on the upper surface or on one side of the pedicel, and producing on the other side an opening in the form of a funnel, projected into the interior of the utricle, and having its exterior aperture closed by a fringe of hair attached to the upper margin. The interior surface of the funnel is adorned with differently shaped and elegant hairs, disposed in regular order. All the interior surface of the utricle is likewise covered with hairs composed of two cells, each of which is prolonged into two appendages of unequal length (Schleiden, loc. cit.).
* De Candolle, “ Physiologie Vegetale,” t. xi., p. 87. + “ Botanische Zeitung," 1847, p. 721. I Ibid., 1848, p. 17. “ Grundzüge der Wissenschaft, Botanik,” 338, iv. Auff.
Beitrage zur Anatomie,” etc. “Denkslinflen der K. Bair. Bot. Gesettschoft," 1859, B. iv. 153.
Benjamin explains the formation of these utricles by supposing an arrest of development in certain segments of the leaves; instead of elongating themselves, they increase in breadth; a constriction takes place, forming a narrow neck, and they appear as little globular bodies, attached by a short pedicel to the vein of the leaf. According to Benjamin, we can follow these phases of formation by examination of a single leaf from its base to its summit. The utricle, at first filled with protoplasm, becomes, by the rapid absorption of this fluid, a reservoir of air, and, stretching in all directions, gradually assumes its ultimate form, which somewhat resembles a stomach, the pedicel taking the place of the pylorus, and the opening of the caudiac orifice. T'he mouth of the utricle he represents as a valve opening inwards. ...
Schacht regards those organs of the Bladderworts, which most botanists consider leaves, as leaf-bearing branches, which, in their young stages, are rolled up, like the fronds of ferns; under this crook, their leaves are formed in succession, and in their axils small conical bodies appear, composed of little cells, like the beginning of a bud. These small bodies soon exhibit at their rounded extremities little cavities, produced by an arrest of the development of their cells, the margins of which grow, and the little cellular body, at first sessile, afterwards exhibits a prolongation at its base in the form of a pedicel. The lateral walls of the young utricle develop more and more, and the air cavity becomes bigger, the margins of the lateral walls incline towards each other, and fold inwards, while the original aperture closes. The original opening is, in fact, & valve, formed by a fold of the margin of the aperture; and the beard which, according to Schleiden, closes the opening, is found later on the external surface. ... Thus Schacht considers the utricles as modifications of the ramifications of the axis, and not of the leaves.
In April, 1867, I studied the formation of the utricles of