OCR Text |
Show 834 ON REMAINS OF CYON FROM SARDINIA. [Dec. 4, Canidae, Winge pointing out, moreover, transitional forms between both. With regard to Lycaon and Cyon, their closer relation with each other than with Canis, as shown by the skull and dentition, is a very striking fact and can scarcely be regarded as a mere parallelism. Huxley observes (P. Z. S. 1880,p. 276)that" in the breadth of the prsemolar region of the upper jaw, and in a more or less marked convexity of the facial contour, Lycaon strongly reminds one of Cyon;" whilst Mivart shows that Lycaon agrees with Cyon in having large incisive foramina and strongly sigmoid external margins of the nasals (A Monograph of the Canidae, p. 196, 1890). Nehring was aware (Sitzungsber. naturf. Freunde, 1890, p. 20) that tbe lowrer carnassial of Lycaon agrees with Icticyon and Cyon in its unicuspid talon. A similar agreement exists with regard to the lower m 2, which in Lycaon is quite as reduced in form as in several lower jaws of Cyon. In tbe former, this tooth has two roots; but this condition also occurs quite as often in Cyon as the presence of only one root. The lower m 3 reappears very rarely in Cyon (Van der Hoeven) ; conversely in one of the five .skulls of Lycaon in the Natural History Museum this tooth is missing. In the upper jaw, m 1 of Lycaon is reduced almost to tbe extent of Cyon, and m 2 is also reduced more than in Canis. Therefore, in m y opinion, Lycaon and Cyon are much more closely allied than has hitherto been supposed. The first recorded Pleistocene Carnivore of this Canine type is Studiati's Cynotherium sardoum (1857), from the ossiferous breccia of Bonaria near Cagliari, well described by Studiati, who, however, was not aware of its affinities with Cyon. These were pointed out by myself in 1872. and later on (1877) corroborated by figuring some of Studiati's specimens side by side with Canine remains of the ordinary type. The specimens from the two Sardinian localities agree with Cyon bourreti Harle, from the cave of Malarnaud (Allege, France), in the conformation of the lower posterior premolar (p 1), which is the same as in the recent species of Cyon; whereas the same tooth of Cyon europceus Bourg., from caves of the Maritime Alps and Moravia, exhibits a strongly developed anterior basal cusp, which is a characteristic feature of Lycaon, and therefore acquires additional interest iu connection with the above remarks on the relationship of both genera. With each other the Sardinian fossils agree in the absence of tbe lower anterior premolar (p 4) and in tbe presence of a diastema between p 2 and p 3. These tw7o characters are certainly of specific, but not of generic value. As I formerly pointed out, the establishment of a separate genus, Cynotherium, appears to be unnecessary ; the characters upon which Studiati insisted for generic distinction are those of Cyon and Lycaon. Pending more complete materials, tbe latter genus may be excluded on account of the couformation of the lower p 1 and of the more slender build of the teeth generally. The present Sardinian Carnivore will accordingly have to be known as Cyon |