44 



proceeds. Nearer to tlie external auditory meatus than the 

 metatragus of the taxonomist is a second and smaller process 

 of the antihelix which, by becoming separated from the main 

 proc-ess with the enlargement of the auricle, leads, in the 

 adult, to the formation of a pit between the two processes. 

 The ''deep hollow" described in this area of the adult ear 

 is, however, a secondary feature formed by the relative growth 

 of the surrounding parts. 



Two genuine pockets are, however, present in the auricle. 

 The first is the common mammalian pocket in the posterior 

 portion of the helical margin, and which is generally known 

 as the sulcus auris posterior. Tlio second pocket is a remark- 

 able one (mark'ed A in figs, 7 and 8) in the centre of the 

 developing tragus. This tragus pocket becomes covered by the 

 hair of the cheeks in the adult, nevertheless it remains a 

 permanent and remarkable feature of the external ear. 



Manus. — The digital formula is 2 = 3>'4>>5>»1. Claws 

 are developed at the 17 mm. stage upon digits 2, 3, and 4; 

 but 1 and 5 are clawless. The digits are fusiform, tapering 

 towards their distal extremities; there are no definitely 

 developed apical pads. Three basal pads are developed, one 



Fig. 8. 



Form of the external ear (from 



Specimen Male B, Perth). 



being opposite the base of each clawed digit. The skin of the 

 palm is granular (see fig. 9). ,— w. 



Pes.— The digital formula is 4>5>2:3>1. 



The outstanding features of the foot are the great size 

 of the fourth digit and the reduced condition of the first, 

 which bears no claw. The digits are fusiform. Three basal 

 pads are present, one being at the base of digit 5, a larger one 

 at the base of 4, and a small one at the base of the syndactylous 

 elements. 



