SUPPLEMENT. 305 



Order CARNIVORA. 

 Suborder CARNIVORA PRIMIGENIA. 



It appears advisable to notice the chief characters of the Suborder '. 



Homology and number of the teeth following the Eutherian type 

 (i. e. there are usually four premolars, and neither the true molars 

 nor the incisors exceed three in number); pm. 4 and mTl not 

 differentiated into distinct carnassials ; true molars often structurally 

 like those of the Polyprotodont Marsupialia; a complete milk- 

 dentition ; no palatal vacuities or inflection of the angle of the 

 mandible ; brain-cavity small ; a third trochanter frequently present 

 in the femur ; scaphoid and lunar generally separate 2 ; absence of 

 a distinct groove ou the tibial facette of the astragalus 3 . 



Family HY^NODONTID^ (pt. i. p. 20). 

 The scaphoid and lunar were apparently united in at least one 

 genus (? Hycenodon) *. 



Genus HYJENODON 3 (pt. i. p. 21). 

 Hysenodon leptorhynchus (pt. i. p. 26). 



M. 2346. The greater part of the associated cranium and mandible; 

 (Fiy.) from the Phosphorites of Cay lux (Tarn-et- Garonne), France. 



1 For an amended arangement see Schlosser, ' Morphol. Jahrb.' vol. lii. 

 pp. 287-294 (1886). This writer regards the group as of equivalent value with 

 both Oarnivora and Insectivora ; but the view adopted in pt. i. is to use the 

 term Carnivora in a wider sense, and to regard its three Suborders as ap- 

 proximately of equal value with the Suborders of the Ungulata. It may be ques- 

 tioned if, on this view, the Insectivora can be distinguished from the Oarnivora, 

 although they apparently pass in the other direction into the Lemuroidea. 



2 See note 4. 3 Grooved in Mesonyx. 



4 See pt. i. No. 26752 ; No. 27583 on the same page also has a scapho-lunar. 

 There are no other Carnivora from the Vaticluse beds to which these specimens 

 could have belonged, and they were evidently associated with the hind feet 

 showing the ungrooved astragalus characteristic of the Suborder. From its 

 specialized dentition it is probable that these bones belonged to Hycenodon 

 rather than to Pterodon. On account of Gervais's reference of a scapho-lunar to 

 Hycenodoji, Schlosser (op. cit.) refers that genus to the Carnivora Vera, but its 

 dentition is too like that of Pterodon to admit of this view. According to Scott 

 (see Cope, ' Amer. Nat.' vol. xx. p. 966 [1886]), the scaphoid and lunar are distinct 

 in the American species of Hyanodon, but there is no reason why they should not 

 have united in the European forms ; since an analogous instance occurs in the 

 case of the N.- American Anchitherium bairdi, where the meso- and entocunei- 

 form remain distinct, although they have united in the French A. aurelianense. 



5 In reference to the note in pt. i. p. 21, as to the number of upper cheek- 

 teeth in this genus, the writer finds that Filhol has recorded in the 'Ann. Soc. 

 Sci. Phys. Nat. Toulouse,' 1882, p. 18, the absence of m. 3. See also ' Ann. 

 Sci. Gt-ol.' vol. viii. art. 1, p. 16. 



PAKT V. * 



