CHAP. IV] THE GENERAL ANATOMY OF THE CERCOPITHECIDAE 127 



of the palm of the hand. Special attention must be directed, 

 however, to a feature ascertained (by Schlaginhaufen) to distinguish 

 the Macacus group of Cercopithecidae, and with these most of the 

 Catarrhinae including Man, while the Cynocephalous apes alone 

 stand out in marked contrast with all their associates. 



The feature in question is the course pursued by a certain line 

 (marked R l3a ) on the plantar surface (Fig. 79). This line (R 13a ) 



Fig. 78. Macacus nemestri- 

 nus. Scheme of the cutaneous 

 grooves of the foot as shewn 

 in Fig. 77. (From Schlagin- 

 haufen.) 



.-), triradius. 



7>! , B., etc., lineae fcerminales. 



C, agmen principale. 



D, triradius secundarius. 

 -E n E. 2 , agmina secundaria. 

 F, figura tactilis. 



should be traced from the tri-radius (T 13 ) whence it starts at the 

 base of the first interdigital pad. It passes hence towards the heel 

 with a bold sweep, and finally it is recurved towards the tibial 

 margin. Such is its characteristic (though not invariable) course in 

 the majority of the Catarrhinae. But in the Cynocephali it may be 

 observed to cut clean across the plantar surface to gain the fibular 

 border. (In such a case, the remaining three interdigital eminences 

 are isolated from the proximal eminences by a series of transversely 



