5 i6 



RHYNCHOCYON AND PETRODROMUS 



CHAP. 



are five fingers and toes. There is a caecum as in but few 

 Insectivores. The tooth formula, as revised by Thomas, 1 is 

 I - C \ Pin M - 2 --g, the total number being thus forty or 

 forty-two. There are several species of this genus. 



Fia. 250. Rhynchocyon chrysopygus. x . (After Giinther.) 



Rhynchocyon and Petrodromus differ from Macroscelides in 

 not having such long hind-legs. The dental formula of the 

 first is I-MP C ]- Pmf Mf = 34 or 36, of the latter If C i- 

 Pm 4- M = 40. In Petrodromus the toes are reduced to four ; 



4 ^ 



in Rhynchocyon there are only four digits in the manus as well 

 as in the pes. This animal, as its name implies, has a longish 

 proboscis, which can be bent, and is really very like a miniature 

 Elephant's trunk, and also like that of the Desman (Myogale}. 

 It has thirteen pairs of ribs, and a well-developed caecum. Dr. 

 Giinther has pointed out that in Petrodromus tetradactylus the 

 hairs of the lower part of the tail are stiff elastic bristles 5 mm. 

 long, with a swelling at the free tip. The use of this singular 

 modification is not at all apparent. Pseudorhynchocyon, of 

 European Oligocene, is believed to be related to this family. 



Fam. 8. Talpidae. This family is confined to the Palaearctic 

 and Nearctic regions, or practically so, being fairly equally dis- 



" Mammals collected by Dr. Emm Pasha," in Proc. Zool. Soc. 1890, p. 446. 



