264 



PHYSIOLOGICAL SERIES. 



D. 325. The brain of a Bush Dog (Speothos venaticus), ( ? ). 



A complete ectosylvian arc is present only on the ri^ht 

 side, and even there its anterior limb is short and appears 

 to be joined to the " Sylvian fissure." On the left side 

 the small posterior ectosylvian sulcus joins the pseudo- 

 sylvian a short distance below the apex of the hitter. 

 A comparison of this condition with that of the Viverrida; 

 is interesting. 



Fig. 141. 



-SULC. ECTOUT. 



The postlateral sulcus is absent on the right side ;m<l 

 represented merely by a shallow pit on the left side 

 (fig. 141). O.C. 1325 id. 



Mivart, Journ. Linn. Soc., vol. xix. 1886, p. 4. 



D. 326. The brain and upper part of the spinal cord of a Dog 

 ( Cants familiaris) . 



The cerebellum has been removed, the corpus callosuiu 

 cut through, and the cerebral hemispheres widely divari- 

 cated. Upon the left side a portion oi th- pons Yarolii 

 has been cut away to demonstrate flu- continuity of the 

 pyramidal tract with part of the crus cerebri. 



The lateral ventricles have been opened ><> as to show 

 the corpora striata, each of which is separated from the 

 optic thalamus by a deep oblique furrow. On the right 

 side the optic thalamus is to a great extent hidden by the 

 upper extremity of the hippocampus and tin- t'ornix pro- 

 ceeding forward from it. < >n tin- lefl i!e tin- thalamns 

 has been expox-d l.\ tin- removal ol part of the fornix and 



