NERVOUS SYSTEM. VERTEBRATA. 255 



On the left hemisphere of the first specimen (fig. 125), the 

 " Sylvian fissure " is an extremely short notch in the upper 

 lip of the rhinal fissure and the posterior ectosylvian sulons 

 (which is independent of the anterior ectosylvian) ends 

 in very close proximity to this small pseudosylvian. On the 

 right hemisphere the pseudosylvian is larger and surrounded 

 by a distinct ectosylvian arc (fig. 126). In the left hemisphere 

 of the second brain (fig. 127) there are two " Sylvian notches," 

 o which the longer overlaps the posterior ectosylvian so that 



at a casual glance they might easily be mistaken for one fissure. 

 On the right hemisphere (fig. 128) a similar arrangement of the 

 only " Sylvian element " is found. Figure 129 represents yet 

 another variety. These specimens clearly show the real nature 

 of the pseudosylvian sulcus, or " Sylvian fissure " so-called, in 

 the Viverridse.] 



D. 307. The brain of an jJCvisa (Crossarchus obscurus), ( ? ). 



This may be regarded as a simplified Herpestine brain. 

 The " Sylvian fissure " seems to be absent in this 

 specimen. 0. C. 1325 I b. 



D. 308. The brain of a Palm-Civet (Paradoxurus typus), ( ? ). 



There is a typical " feline Sylvian fissure " ; orbital and 

 posterior ectosylvian sulci as in the Felidse and Hysenidse ; 

 a typical suprasylvian sulcus forming a regular arc with 

 the postsylvian ; conjoint coronal and lateral sulci without 

 any ansate ; and no true crucial sulcus. There are, how- 

 ever, some shallow pits, where the crucial sulcus occurs 

 in other brains, and the coronal sulcus has an unusual 



