OCR Text |
Show 182 PROF. ST.-GEORGE MIVART ON THE ALUROIDEA. [Feb. 7, If perfect, it is very short. The opening of the external auditory meatus is small and triangular, and, as it were, somewhat cut away below; and there is a deep groove and a defect of ossification on the floor of the anterior chamber of the auditory bulla. The frontal postorbital processes are well developed ; and the skull is much pinched in behind them. There are small pointed malar processes; but these do not nearly join the former. The condyloid foramen is concealed. The cranial ridges are moderate. The paroccipital process does not depend. The mastoid is much as in Herpestes, as also is the carotid canal; and there is a conspicuous carotid foramen in the basis cranii; and the artery enters the skull beside the posterior boundary of the sella turcica. The palate is greatly prolonged behind the last molars. In C. fasciatus the cranial characters are similar, except that the short alisphenoid canal is better marked, the palate is rather less prolonged, and the postorbital processes more nearly join, and there may be but a very minute foramen instead of a slit beneath the auditory meatus. The dentition of C. obscurus is represented by De Blainville (Osteog., Viverra, pl. 12). Its -A- is quite two thirds the size of -J-, but is triangular, not quadrate. - ^ is less trihedral than in Herpestes, and has two equally developed external cusps, external and parallel to which is a raised straight cingulum. There is a large internal cusp; and the hinder border of the tooth is concave. - has a rather diminished posterior tubercle (compared with Herpestes) ; so that the large inner cusp is placed rather more towards the middle of the tooth, the length of which is rather less in proportion to its breadth. The inner cusp also descends as much as do the outer ones; and the outer middle cusp scarcely descends below the anterior outer cusp. -*- and ~ are as in Herpestes. ^- is wanting. ^ is large, with five cusps. In ^ the anterior cusp has become more decidedly internal, so that we have an external cusp opposite the internal one. There is a moderate talon, p-j- has one very large cusp, in front of which may be a well-developed or a minute accessory cusp, while behind it there is a well-developed cusp, which has a more or less marked talon or minute accessory cusp at its base, p-y and p-^ are as in Herpestes. p j is absent. In C. fasciatus, ^-2 is rather smaller in proportion to Hiia and ~ and ^ are larger. In a specimen in the British Museum, labelled Mungos gambianus (No. 55. 12. 24. 22 b), - and " are very narrow antero-posteriorly. In another skull, labelled M. zebra (No. 75. 2. 24. 18), there is a minute - on each side, which measures 0"*1 antero-posteriorly and 0"*25 transversely. The dimensions of the skins seen by me are as follows :-of C. obscurus, head and body about 37", of tail 17" ; of C.fasciatus, head and body about 45"*5, of tail about 23". |