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differs from the other two in the small size of its teeth. In the upper jaw, Premolar 2 is characterized by the presence of the anterior accessory cusp, and by the large development of the posterior one; Premolar 3, by the presence of both these, which are absent or rudimentary in the other two species; Premolar 4, by the division of its sectorial edge into three subequal lobes. But the oblong transverse tubercular upper true molar exhibits the maximum differences, in its implantation by three fangs. According to M. De Blainville, it possesses but one fang ("na' qu'une racine "), on the authority of Frederic Cuviert ("elle a plus de deux racines") more than two, while all those that I have examined in the British, Hunterian, and Oxford Museums, without exception, possess three, situated very nearly in the same transverse line. Its crown is composed of three tubercles, inter-connected by a ridge, the stouter on the inner side, and each supported by a fang.

In the lower jaw, the accessory cusps are much more strongly marked in the Premolar series, than in the other species, while the true molar exhibits considerable differences of size and form. The tubercular portion is developed largely at the expense of the carnassial, the blades of which are subequal in antero-posterior extent. On the inner side, and springing from the posterior of these, is a stout cusp or tubercle, the analogue of that in the Canidæ.

B. The dentition of the species which comes next to the former, H. brunnea, Thunberg — (H. fusca of Geoffroy, Crocuta brunnea, Gray, H. villosa, Smith), offers very considerable points of difference, the principal of which are the large development of the posterior lobe of the upper sectorial, and the small size and triangular form of the upper true molar. The latter, in its implantation, also differs from the preceding species. In the Royal College of Surgeons (Hunt. Cat. 4447), and in the British Museum (822 B. Gray's Cat.) it is supported by two fangs, while in a second specimen in the latter Museum (822 A. Gray's Cat.) it possesses but one.

In the carnassial of the lower jaw, the posterior blade is longer in antero-posterior extent than the anterior; the cusp springing from its inner base is reduced to a minimum, and the tubercular portion is very feebly developed.

N.H.R.-1865.

Osteographie, Article Hyena, p. 27. † Oss. Foss. tom. iv. p. 236, 4to. 1823.

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In the premolars of both upper and lower jaw, the principal cones are developed at the expense of the accessory ones.

C. The third species, H. crocuta, Bodd. (Crocuta maculata, Gray, H. Capensis, Desm.) ranging through South Africa, the Guinea Coast, and Senegal, is very closely allied to the preceding in its dentition, so closely indeed, that Professor Owen has entered a skull of the former in the Hunterian catalogue (No. 4447), as belonging to the latter. In the specimens in the British Museum, the basal ridge on the inner side of the upper Premolar 2, and the lower Premolars 3, 4, is more strongly developed than in H. brunnea. But the most important characteristic is the absence of all trace of the cusp at the inner and posterior base of the lower carnassial. The tubercular portion of the latter, reduced to a small talon, is divided by a slight ridge into two portions of which the exterior is the smaller.

On the authority of M. De Blainville,* the upper true molar is very small and subtriangular, and, according to Professor Owen,† is implanted by two fangs.

§ 2. Having thus noted the differences which obtain in the three recent species of Hyenas, we are now in a position to turn to the analysis of the Fossil species. So far back as the year 1839, the fact that the H. striata, or more dog-like of the existing hyenas, was represented in the bone caverns of France, was proved by the discovery of H. prisca by Marcel de Serres,‡ in the caverns of LunelViel. Nine years after this, the existence of the second or intermediate species H. brunnea in Auvergne, was shown by the labours of §MM. Croizet and Jobert, in the discovery of H. Arvernensis. Irrespective of size, the differences between the recent and the fossil species, in each of the above cases, would by no means warrant a specific distinction. M. De Blainville refers both these to H. striata, or the Striped Hyena, including H. brunnea also under the name of H. fusca in the same species. And, lastly, we owe to our great explorer of caves, Dr. Buckland,|| the proof that the third or most Feline of the recent species, H. crocuta, was

* Osteographie, Art. Hyena, p. 29.

† Brit. Foss. Mam. 8vo. 1840, p. 150.

Recherches sur les Oss. humatiles des Cavernes de Lunel-Viel, par Marcel de Serres, Dubrucil et Jeanjean, 4to. 1839.

§ Recherches sur les Össemens Fossiles du Puy de Dôme, 4to. 1484, p. 198, pl. 1. fig. 4. Reliquiæ Diluvianæ, 4to. 1824.

represented in the caverns of France, Germany, and England, by the Spelman Hyena.

Of the relation of H. Monspessulana of Christol, to H. prisca, and of H. Eximia, mentioned by M. Gaudry (Bul. Soc. Geol. de France, 1862-3, 2 Series, tom. 20, p. 404), to H. brunnea and H. Arvernensis, we can say nothing.

The equivocal premolar found in Auvergne, upon which the provisional species H. dubia* (Croizet and Jobert) is based, and that found in the Red Crag of Suffolk, and described by Mr. Lankester under the name of H. antiqua,† differ to such an extent from any known or extinct species, and bear such an exceptional character, that we must wait for further evidence before discussing their merits.

The fossil species which now remain to be discussed, are the H. intermedia‡ of Marcel de Serres, and the §H. Perreri of MM. Croizet and Jobert. And as the question of their validity as species is most essentially connected with the accurate definition of the dental characteristics of H. spelæa, it will be more convenient to treat of them along with the latter.

§ 3. A. The following notes upon the deciduous dentition of H. spelæa, are based upon an examination of two upper jaws in the British Museum, and two in my own possession, and of five lower jaws and numerous isolated teeth. The pair of jaws figured (fig. 1 & 2), containing the entire unworn milk molar series, were obtained by Mr. Ayshford Sanford, F.G.S. and myself in Wookey Hole Hyenaden in our further exploration of 1863. They were lying imbedded in the red earth, with which the cavern was filled, within a few feet of each other, at the point where the passage B. joins the Antrum in the ground plan given in the Quarterly Geological Journal,|| and close to a mass of breccia, containing fragments of calcined bone and one roughly chipped splinter of greensand chert. Their state of preservation shows that they belonged to the same individual, which probably, from the teeth marks on the lower jaw, fell a prey to some of its older and more powerful fellows. The fragments of album græcum which fill up the alveolus of the lower true molar, prove also that the jaw was lying on the coprolite covered floor of the cave for some time previous to its being imbedded.

*Op. cit. p. 181. pl. 2. fig. 4.

† Annals and Magazine of Natural History, Series 3, vol. xiii. No. 73. Op. cit. p. 88.

Op. cit. p. 173, pl. 1, fig. 12. pl. 11, fig. 3.

Vol. xix. p. 261.

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Dm. 1. (See fig. 1. & 2.) The first milk molar of the upper jaw presents a trenchant conical crown traversed by a slight ridge, that

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divides the latter into two equal halves. Anteriorly at its junction with the cingulum it is slightly thickened. On the posterior aspect of the crown, which, as in the Canidæ, is longer than the anterior, is a well defined notch marking off a small cusp. The cingulum is more strongly marked behind than before, and in the British Museum specimens is also largely developed on the inner side. The crown is supported by two cylindrical divergent fangs, and is implanted obliquely in the jaw, to admit of the crowding of the small Premolar 1 into the alveolar border.

Dm. 2. The second milk molar, as is usual in the carnivora, con

sists of a sectorial and tubercular portion. Anteriorly are two small trihedral cusps, situated obliquely and separated from each other by

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a notch (fig. 2). The outer of these is separated from the anterior blade by a slight depression, the inner by a cleft. The anterior recurved blade is the higher. Its trenchant edge shorter than that of the posterior, offers a point of contrast with the corresponding portion of its homologue in H. striata, where the trenchant edges are of both blades subequal. A small obtusely pointed cusp, the "inner tubercle" of Prof. Owen, is developed from the middle of the inner base of the anterior blade, as in the representative tooth (Pm. 4) of the Cats, Dogs, Civets, Gluttons, and Zorillas, and extends a con

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