NERVOUS SYSTEM. VERTEBRATA, 



391 



Above the calcarine there is in this specimen no trace of 

 a parieto-occipital sulcas ; further downwards, however, 

 there is a short and obliquely-placed calloso-marginal 

 sulcus. 0. C. 1337 E. 



D. 560. The brain of a Three-banded Dourocoli (Nyctipithecus tri- 

 virgatus). The left cerebral hemisphere has been separated. 



In spite of its damaged condition this specimen has been 

 retained because it exhibits in an especially clear manner a 

 rhinencephalon with the typical features such as we find in 

 mammals other than Primates and which are not usually 

 so clearly demonstrable in the Anthropoidea. 



Note the absence of central sulci. The sulcus rectus is 

 also very poorly developed. 



The dorsal limb of bifurcation of the calcarine is so 

 diminutive that at a casual glance the sulcus resembles the 

 unbranched condition found in the Marmosets. 



D. 561. The brain of a Lemurine Dourocoii (Aotus felinu*). 

 The left hemisphere has been detached. 



This brain resembles the preceding specimen. Note, how- 

 ever, that the calcarine complex presents the usual Y-shape. 



0. C. 1337 E o. 



D. 562. The brain of a Lemurine Dourocoli (Aotus felinus). 

 The left hemisphere has been separated. 



This brain resembles the two previous specimens. There 

 is, however, a small central sulcus and a very faint rudiment 

 of a parieto-occipital sulcus. 0. C. 1337 E b. 



D. 563. The brain of a Lemurine Dourocoli (Aotus fell 111/5), 

 The left hemisphere has been detached (fig. 229). 



Fig. 229. (Nat. size.) 



S-.; RIMfM 



s..: :^= 



SULC. FAR 



This specimen resembles the preceding. 0. C. 1337 E c. 



