127 



The Rhinarimn. — Tbe rhinarium is roughly triangular 

 in shape and distinctly grooved in the middle line-. The 

 surface is finely granular. The narial slits are bounded 

 above entirely by naked skin, but their lower margins are 



Fig. 11. 

 Left pes, 35 mm. stage. 



pubescent behind. The infranarial portion of the rhinarium 

 runs to the upper lip, forming a very definite portion of its 

 medial area, (see fig. 6). 



The External Ear (see figs. 7 and 8). — In all stages 

 which I have examined the auricle has been folded back- 

 wards. This is true of the 35 mm. embryo. The whole 

 process of the development of the pinna may be described 

 as a progressive simplification. Two well processi antihelicis 

 appear, but only one persists as a meatal operculum. A 

 well-marked bursa in the 80 mm. embryo becomes reduced 

 to an insignificant depression in the 105 mm. stage. Of the 



Lm 



