256 APPENDIX. 



Genus 25. Arctemys. Feet and tail short; nails robust; inferior inci- 

 sive subulate. 



Genus 26. Sciurus. Hind feet turned towards each other; nails very 

 sharp; tail long and bushy; inf. incisive much compressed. 



Genus 27. Pertmys. Tail long and bushy; skin of the flanks extend- 

 ed between the fore and hind limbs. 



FAMILY ACULEATA. 



Genus 28. Hystrix. 



FAMILY DUPLICIDENTATA. 



Genus 29. Lepus. Hind limbs very long: ears very long: tail short. 



ORDER PECORA. 



FAMILY CAVICORNIA. 



* Nucleus of the horns solid. 

 Genus 30. Antelope. 



** Nucleus of the horns cellular. 

 Genus 31. Ovis. Tail destitute of terminal tuft. 

 Genus 32. Bos. Tail ending in a bushy tuft. 



FAMILY CAPREOLI. 



Genus 33. Cervus. 



ORDER CETE. 



FAMILY SIRENIA. 



Genus 34. Manatus. Body oblong, ending in an oval, horizontal 

 fin; pectoral fins furnished with rudiments of nails. 



Genus 35. Stellerus. Body elongated, ending in a crescent shaped fin; 

 no rudiment of nails. 



FAMILY HYDRAULA. 



Genus 36. Delphinus. Head proportioned: teeth. 

 Genus 37. Monodon. Head proportioned: no teeth. 

 Genus 38. Physeter. Head exceedingly disproportioned: teeth. 

 Genus 39. Balsena. Head exceedingly disproportioned: teeth carti- 

 laginous, or rather cartilages instead of teeth. 



