1885.] DR. ST. G. MIVART ON THE AHCTOIDEA. 341 



more truly cylindrical, and longer than in other Carnivora. In the 

 Dogs there is no trace of the anterior descending process of the 

 temporal bone, which in the JMustelas confines the condyle of the 

 lower jaw ; in other Carnivora there is always a slight trace of the 

 process, but in none does it enclose the condyles, as in most of the 

 Mustelidce. 



"The genera contained in this family are Mustela, Zorilla, 

 Galictis, Bell (which must not be confounded with the Galictis of 

 Is. Geoffroy St. Hilaire, pubhshed in the ' Comptes Eendus ' for 

 October 1837, p. 581), Mellivora, Vvsitaxus, Helictis, and Gulo, in 

 which the true molar of the upper jaw is transverse; Lutra and 

 Mephitis, in which the tooth approaches more or less to a square 

 form ; Taxidea, in which it is triangular ; and, lastly, Meles, Arctonyx, 

 and Mydaus, in which the true molar is longer than broad. 



" In the Ursidce there are two well-developed true molars on 

 either side of each jaw ; the ' carnassiere' ' here has changed its 

 functions, not being suited, as in other Carnivora, to cutting flesh. 

 The palate is considerably elongated. In the Bears {TJrsus and its 

 subgenera) it is small, being robbed as it were of its nutriment by 

 the true molars, which are very large. In the other Ursidce (Pro- 

 cyon, Nasua, Cercoleptes, Arctictis'^, and Ailurus), the ' carnassiere,' 

 especially that of the upper jaw, and the true molars are nearly 

 equal in size, and also nearly resemble each other in other re- 

 spects. ^ 



"In the true Bears the form of the lower jaw differs from that of 

 any of the preceding Carnivora in having a projecting process on 

 the underside of the ramus, and situated a little in advance of the 

 angle of the jaw. The same character is also found in many Seals, 

 which in several other respects appear to approach the Bears." ^ 



Mr. Waterhouse's two families Mustelidce and Ursidce were united 

 by the late Mr. H. N. Turner ' into the single family Ursidce, v{\\\c\i 

 was equivalent to the group here designated Arctoidea, and which 

 he divided into the four subordinate groups (I) Ursina, (2) Ailu- 

 rina, (3) Procyoiiina, and (4) Mustelina. As to these groups, Mr. 

 Turner has expressed the following views, and made the following 

 observations : — 



" In the Ursina we find no trace of a pterygoid fossa, the outer 

 pterygoid process being closely pressed against the inner one, or 

 true pterygoid bone, and sending off a strong lamina of bone to 



' The " carnassiere '' is the sectorial tooth, i. e. the fourth uppar premolar, 

 against which the lower sectorial, or first lower true molar, bites. 



- That Arctictis is not an Arctoid but an .'Eluroid is now imiversally knowa 

 and admitted, though De Blainville figures it amongst the members of his 

 genus " Suhur»us." 



^ Mr. Waterhouse adds in a note: — " From an examination of the external 

 characters of Bas^aris asfuta, it appears to me that it belongs to this group," 

 i. e. to the Ursidm. 



* I have thought it worth while to reprint this extract, as being of so old a 

 date as to have a certain historical interest, and because many Fellows of the 

 Society may not possess the 'Proceedings' of so many years ago. 



» P. Z. S. 1848, pp. 75-8fi. 



Proc. Zool. Soc— 1885, No. XXIII. 23 



