22 



MB. R. I. POCOCK ON THE EXTERNAL 



I have not been able to examine in a fresh state the rhinafium 

 of any species of Indrisidse. 



The muzzle of Tarsius is very different from that of all Lemurs.. 

 The only trace of the rhinarium, if such it can be called, that 

 remains is a narrow rim of naked skin surrounding the nostrils, 

 which are widely separated as in the Platyrrhine Pithecoid 

 Primates. The nose scarcely projects at all, and the muzzle is 

 squarely truncated and deep, and the upper jaw hardly overhangs 

 the lower, so that in profile view the muzzle has a decidedly 

 feline appearance, contrasting markedly with the generally 

 canine appearance of that of the true Lemurs. The long upper 

 lip is undivided and continuously hairy from side to side across- 

 the middle line, and its frenum is set higher above the incisor 

 teeth, suggesting that the lip is susceptible of partial protrusion 

 after the manner of the lip of the pithecoid Primates, but to a 

 lesser degree (text-figs. 1, E ; 2, A). 



The primitive muzzle of the lemuroid Primates, with its 

 rhinarium and adherent upper lip, is associated with the habit of 

 drinking by means of lapping. The specialised muzzle of the- 

 pithecoid Primates with aborted rhinarium and protrusible 

 upper lip is associated with the habit of drinking by means of 

 suction. But Tarsius, although more resembling the pithecoid* 

 in the structure of the muzzle, drinks, it is said, by the lapping 

 method*. This fact is full of interest in connection with the 

 view, supported by other considerations, that Tarsius links the- 

 Lemuroids and Pithecoids together. 



The Ear f. 



In the species referred to Lemur the pinna of the ear is 

 tolerably uniform in shape and structure. It is small and con- 

 cealed to a greater or less extent by its own hairs and those of 

 the surrounding area of the head. Its superior posterior edge is- 

 not folded ; but the anterior edge of the upper half forms a 

 strong ridge overlapping the anterior end of the simple shelf-like- 

 supratragus (plica principalis) and descending below it and 

 vanishing in the capsule of the pinna above and within the 

 small lobate tragus. The antitragus is somewhat larger than 

 the tragus, sometimes much larger (Lemur caita) ; and the deep 

 notch between them is approximately on a level with the external 

 auditory meatus. The flap of the ear behind the antitragus is 

 marked with a depression, the anterior and posterior margins of 

 which are respectively the ridge running upwards from the anti- 

 tragus and the adjoining postero-inferior edge of the pinna. 

 The supratragus, forming the upper boundary of the capsule of 



* H. Cuming, P. Z. S. 1838, p. 67. Mr. Cuming also makes the interesting 

 remark that when any object is put near a Tarsius, the animal " draws up the 

 muscles of the face similar to a Monkey and show its .... teeth." I have never 

 seen Lemurs behave in this way. 



f Described in several types by Mivart and Murie, Tr. Zool. Soc. 1872. 



