40 ' Mammalia. Prohoscidia. 



a second spine. The inner condyle of the humerus is not perforated, except in 

 Ursus ornatus. 



Finnigrada. There is no trace of a Clavicle. The humerus is generally- 

 shorter than the scapula : the inner condyle is perforated in Phoca (? alone). 

 The antihrachial hones are compressed and firmly united. The fore feet are 

 short and expanded into swimming paddles. The poUex or first digit exceeds i\ie 

 third, fourth, and fifth in length, but presents its characteristic inferior nimiber 

 of phalanges. 



The Pelvic arch and Appendages. The Pelvis varies greatly in the 

 three principal Sub-orders, and so also its appendages ; but certain 

 characters appear to be common to each Sub-order, as follows: 



Digitigrada. The ilia are long and narrow, but thick : the ischia are also 

 long : the pubis is short, but the ischio-pubic symphysis long. The whole 

 * innominate ' bone forms a considerable angle with the axis of the lumbar series. 

 The toes alone touch the ground, the heel or calcancum being much raised. The 

 hallux is rudimentary in Vivenidce and Canidae. 



Semi-Plantigrada. Only a part of the hind foot forms a sole to rest on the 

 ground. 



Planiigrada. The ilia are shorter, thicker, and broader, than in the Digiti- 

 grada : the ischia are short and expanded, and form with the strong ^;?</ye a 

 long symphysis: tho fet)iur is remarkable for its groat length, and superficial 

 resemblance to that of Man, though flattened from before backwards. In tho 

 Procyon (Raccoon) the fibula is characterised by three processes behind its distal 

 end. The hallux is rather shorter than the other toes, which are of subequai 

 length, and form the basis of a broad flat foot : the whole of the hind foot forms 

 a sole and rests upon the ground. 



Finnigrada. The Pelvic arch is remarkable for the stunted development of 

 the ilia, and the great length of the ischia and pubes ; the symphysis is short, and 

 divaricable in parturition (cf. v.). 1h.c femur is equally peculiar for its short- 

 ness and breadth ; the shaft almost disappears and the two articular extrcmitiea 

 form nearly the whole mass. The tibia sm^ fibula are anchylosed at their prox- 

 imal ends. The bones of ihafoot are much developed, and are modified to form 

 the basis of a large and powerful fin : in Phoca, the middle toe is the shortest, 

 and the rest increase in length to the margins of the foot ; in Otaria and Trichae- 

 cus the toes are subequai in length. The hind feet are fettered by the continua- 

 tion of the integument to the tail. 



yil. PROBOSCIDTA. 



The Shdl. The Sutures are soon obliterated. The Frontal bone 

 is excessively expanded by air cells ; as also are the short triangular 

 Nasals^ with which it coalesces. The Superoccipital is much expanded 

 and supports two Interparietals, which together with the Parietals, 

 Frontals, and jS"asals, form a dome of considerable size : hence the 

 cranial far exceeds the facial area. This dome is however filled al- 

 most entirely with contiguous air cells, and only a small proportion of 



