334 PHYSIOLOGICAL SERIES. 



D.451. The brain of a Chilian Deer (Pudu pudu), (<?). 



This brain shows features of great interest in com- 

 parison with those of Odocoileus and Capreolus. The 

 suprarhinal operculum is poorly developed and the anterior 

 ectosylvian sulctis forms a short, vertical, paraorbital sulcus 

 which is joined by the true orbital. 



The splenial complex lies upon the dorsal surface in a 

 great part of its course. 



This brain in other respects may be regarded as a 

 smaller and correspondingly much simplified copy of that 

 of Capreolus. 0. C. 1328 E b. 



Family 



D. 452. The brain of a Giraffe (Gira/a camelopardalis). 



In this brain the Sylvian and presylvian regions conform 

 essentially to the same plan as we find in the larger Deer. 

 There is a vertical pseudosylvian sulcus, from the lower 

 end of which the anterior ectosylvian sulcus proceeds 

 forwards parallel to, and a considerable distance on the 

 dorsal side of, the anterior rhinal fissure. This ectosylvian 

 sulcus joins the orbital sulcus anteriorly, and at the junction 

 a large, vertical, paraorbital sulcus is formed, as in the larger 

 Deer. The region between the anterior ectosylvian suleus 

 and the anterior rhinal fissure is a large depressed area 

 marked by vertical sulci and partly hidden by a great 

 dorsal overhanging operculum. 



There is also a large operculum extending towards the 

 rhinal fissure and overhanging the posterior ectosyivian 

 sulcus. This is deeply incised by two radial sulei, whieh 

 may be regarded as compensatory to the pseudosylvian. 



There is a very deep and complete arcuate sulcus, with 

 a lurge, vertical, apical process between the pseudosylvian 

 and supra-ylvian sulci. 



Unlike the condition found in the Deer, the Mipra-vlvian 

 sulcus has a very large, vertical, posterior, descending ranms, 

 in addition to the posterior horizontal ruinus. And the 

 compensatory sulcus is vertical in relation to the former, 

 and not to the latter as in the Deer. The suprasylvian 



