202 PHYSIOLOGICAL SERIES. 



Section CYNOIDEA. 

 Family CANIDAS. 



D. 322. The brain of an Otocyon (Otocyoii megalotis). 



The anterior and posterior ectosylvian sulci meet and 

 form a regular arc around the short Sylvian fissure. This 

 is one distinctive feature of the Cynoidea in contrast to tin- 

 ^Eluroidea. On the left hemisphere there is :i short 

 vertical offshoot from the ectosylvian arc. 



The suprasylvian and postsylvian sulci are united into a 

 regular arc and there is no separate diagonal sulcus. 



The lateral and short postlateral sulci are joined on 

 both sides, and on the left side the lateral joins the coronal. 



There is a well-developed orbital (presylvian) and a 

 short transverse crucial sulcus. 



Midway between the postsylvian and postlateral sulci 

 there is a short vertical " ectolateral " sulcus. This is a very 

 characteristic feature of the Cynoid brain. 0. ( !. \'.\'2~> M. 



Gervais, Nouv. Arch. Mus., t. vi. 1870, p. 109. 



D. 323. The brain and the upper part of the spinal cord of a 

 ( 'oinmon Fox ( Vulpes vulpes) . 



This specimen exhibits with diagrammatic rlearne.-- tin- 

 typical Cynoid characters : the three regular arcuate sulri 

 (ectosylvian, siiprasylviau. and eorono-lateral respectively) 

 surrounding the short oblique pseudosylvian. The cha- 

 racteristic ectolateral sulcu>. the orbital and the deej.lv- 

 incised oblique crucial sulci complete the picture. There 

 is a small ansate sulcus joined to the coronal on the left 

 side, and an altogether insignificant separate ansate on the 

 right side. 



It will be noted that such other parts of the brain as can 

 be seen in this specimen resemble the corresponding parts 

 in the Cat's brain. 0. C. 1 :\'2' i.. 



Knieg, Zeitsch. f. wiss. Zool., Bd. xxxiii. 1880, p. Ml. 



D. 324. The brain of Canis microtis, in which the left cerebral 

 hemisphere lias been >c|.a rated, (<). 



Ill this specimen we can see the continuity of tbo crucial 



