424 MR. A. H. G. DORAN ON THE MORPHOLOGY 



the neck as in Tragulus napu*. On the inner side of the neck of the malleus of T. kanchil 

 is a small tuhercle-like processus muscularis. The Sylvian apophysis on the end of the 

 long process of the incus is a thick disk, wider in diameter than the end of the processus 

 longus, and pedunculated. 



In the Camelid,e or Ttlopoda (PI. LXI. figs. 10 & 11, Camelus dromedarius) the 

 upper part of the head of the malleus above the articular surface is not much developed ; 

 and, as in the Pigs, it projects forwards, but does not rise above the level of the articular 

 area in an upward direction. This surface is very wide vertically ; its edges are much 

 raised above the level of the rest of the head. The facets are almost plane ; the lower is 

 as long as, but narrower than, the upper ; they run into each other without any trace of a 

 groove. The neck is very short, rather broad towards the head, and very constricted 

 near the manubrium ; there is only a very small fragile lamina stretched between it and 

 the processus gracilis. The manubrium is extremely long, rather slender even at the 

 base, and does not form a very obtuse angle with the body; a bold rectangular projection 

 corresponds to the processus brevis ; the outer aspect is narrow, but sharply bordered, 

 the extremity distinctly spatulate and only a little recurved. 



The incus is very singular and distinctive in form (PL LXI. fig. 9, Lama -peruana). 

 It is extremely high and narrow ; and the anterior part of the body is nearly as deep as 

 the posterior — a rare condition in any Order f. The articular surface is equally distinctive ; 

 it is very wide, corresponding to that on the malleus, and absolutely convex from above 

 downwards ; its margins are very prominently raised above the level of the body ; its 

 lower and anterior extremity stops very far short of the root of the processus longus. 

 Hence the incus in the Camelidse is quite distinct from that of other even-toed Ungu- 

 lates, even from those where it is high and narrow. The stapes has a small narrow 

 head, long and rather slender crura, not very divergent ; and both are inserted some 

 distance from the extremities of the base, which is very thin, particularly in proportion 

 to the same in other Ungulates ; it bears a base of an umbo. 



The malleus of the Camel and Llama are very similar, in the former the head projects 

 more forwards than in its American representative. In Camelus and Lama pacos there 

 is a small, tubercular processus muscularis on the inner side of the neck of the malleus, 

 hardly perceptible in L. peruana. 



In the Prong-buck, or American Antelope (Antilocapra americana, PL LXI. fig. 12), 

 the head of the malleus is very little developed, the upper portion projecting neither 

 upwards nor forwards ; the articular surface is very wide and rather deep, its borders 

 are much raised ; both facets are almost plane ; the upper is very broad ; the lower is 

 narrowed, and is sometimes prolonged into a short tail-like extremity, running onto 

 the neck; but this feature is not constant. I have noticed the same peculiarity 

 in individual mallei of Goats and Antelopes. The groove between the facets is 

 distinct. The neck is very long, cylindrical, and only gently curved, it is joined to the 

 slender processus gracilis by a well-marked lamina. Prom the inner aspect of the neck 

 projects a very stout, straight, blunt-pointed processus muscularis. The slender manu- 



* The processus muscularis is sometimes obsolete in these species. 



t In Camelus the body of the incus is not so high and narrow as in Lama. 



