CETACEA. 139 



SYNOPSIS OF GENERA. 



1. MANATUS. Tail rounded. Grinders f or f , tubercular. 



2. HALICORE. Tail forked. Grinders f, flat tipped; upper 



cutting teeth produced, tusk-like. 



3. RYTINA. Tail forked. Grinders none. 



1. MANATUS. 



Cutting teeth 2, very small, rudimentary, early deciduous. 

 Canine none. Grinders f- -f , with two or three transverse three- 

 tubercled ridges. Lips bristly. Back with scattered hairs. Fins 

 with four rudimentary hoof-like nails. Toes surported with pha- 

 langes. Tail rounded or truncated at the end. Pelvis bone de- 

 ficient ? caecum bifid at the tip. 



Manatus, Rondel, Pise. 490; Storr. Prod. 41, 1780; Cuvier, 

 R. A. ; llliger, Prod. 140, 1811; Rqfin. Anal. Nat. 61, 1815. 



Trichechus, sp. Linn. S. N. ed. 6. 39. ed. 10. ed. 12; Erxleb. 

 Mam. 599. 



Odobenus, pars, Brisson. 



Trichecus manatus, Oken, Lehrb. Nat. 687, 1815. 



? Nemodermus, Rafin. Anal. Nat. 60, 1815. 



The number of grinders varies according to the age or state of 

 the specimens. When complete they are f |, but the three 

 front on each side are often deciduous; hence Home (Phil. 

 Trans. 1821, 390) describes them as f -f, and Cuvier as f-f . 



1. MANATUS AUSTRALIS. MANATEE. 

 Grey black. 



Manatus, Rondel, Pise. 490 ; Klein, Pise. ii. 32 ; Brisson, R. 



Anim. 49, 352. 

 Kleiner Manate (Manatus minor?), Zimmermann, Geog. ii. 426, 



388. 



Lamantin, Condam. Voy. 154 ; Buffon, H. N. xiii. 3/7> 425. t. 57- 

 Trichechus manatus, Linn. S. N. i. 49 ; Gmelin, S. N. i. 60 ; 



Schreber, Saugth. t. 8, cop. Buffon. 

 Manatus australis, Tilesius, Jahrb. i. 23 ; Ozeretskowsky, Nov. 



Act. Petrop. xiii. 375. 1. 13 ; Fischer, Syn. Mam. 501 ; Reichb. 



Syn. Mamm. 16 ; Icon. Cetac. t. 23. f. 72, 73, from Humboldt, 



Anat. Cetac. t. 27, 28, 29. 



Manatus (Trichechus manatus) australis, Illiger, Prod. 110. 

 Manatus Americanus, Desm. Mamm. 507 ; N* Diet. H. N. xvii. 



262. t. 96 ; Home, Lectures Comp. Anat. iv. t. 55 ; Schreber, 



