NERVOUS SYSTEM. VERTEBRATA. 337 



D. 470. A cast of the cranial cavity of a Saiga (Saiga tatarica). 



D. 471. The brain of a Gazelle (Gazella dorcas). 



The " lateral series " of sulci resembles that of the 

 Black-Buck. 



There is, however, no ectosylvian arc, such as we find in 

 the latter. O.C. 1327 06. 



D. 472. The brain of a Gazelle (Gazella subgutturosa] , ( ? ). 



In this specimen it is clear that the intermediate of the 

 " lateral series " of three sulci is the true lateral, and that 

 the large sulcus in the last Gazelle and the Black-Buck 

 must be an unusually pronounced entolateral. 



The crucial-like prolongation of the splenial complex 

 (calcarine and intercalary) joins the coronal sulcus. 



0.0. 1327 c c. 



D. 473. A cast of the cranial cavity of a Gazelle (Gazella scem- 

 merringi). 



D. 474. A cast of the cranial cavity of a Sable Antelope (Hippo- 

 tragus 



D. 475. The brain of a Beisa (Oryx beisa). 



This brain may be regarded as an extremely complicated 

 form of the type found in the Gazelle and Antelope. 

 The complications are introduced by means of numerous 

 additional secondary sulci. 0. G. 1327 c k. 



D. 476. The brain of an Arabian Beatrix Antelope (Oryx beatrix). 

 Note the marked twisting of the mesial part of the 

 cerebellum, which presents such a strong contrast to the 

 symmetrical arrangement of the corresponding part in 

 the Deer. Indications of a similar phenomenon are found 

 even in the brain of a Cephaloplms dorsalis. 0. C. 1327 c p. 



D. 477. A cast of the cranial cavity of .the Nilghai (Boselaphus 

 tragocamelus) . 



D. 478. The brain of a Guib (Tragelaphus scriptus). 



The suprasylvian sulcus is placed unusually high up on 

 the dorsal surface and pursues a sagittal course. It has 

 VOL. II. Z 



