THE BKAIN IX THE EDENTATA. 



293 



a well-developed form in Tamandua (fig. 9), the Dasypodidte and Bradypodidce, and 

 possibly in other representatis^es of the Edentata. A very well-defined fissura rJmiaUs 

 is present to indicate the upj)er bouudary of the pyrit'orm lobe, but it differs very 

 distinctly from that of Orycteropus in that the posterior rhinal fissure joins the anterior 

 rhinal, with which it is continuous, at an angle (fig. 7), wliile the anterior rhinal fissure 



Fia 



bulb, olfact. 



ped. olfact. 



fiss. rhinal. ant 



tnbercul. 

 olfact. 



paraflocc. 

 pons Varol. 



lob. pyrifonn. S 



fiss. rhinal. post 



Lateral aspect of a braiu oi 21yrmecophaya julattt. 



S, Fossa Sylvii. 



Very slightly reduced. 



is still horizontal ; the posterior rhinal inclines obliquely downward and backward, so 

 that it reaches the ventral margin at a point about midway between the vallecula Sylvii 

 and the posterior extremity of the hemisphere ; it then curves inward upon the inferior 

 surface, and ultimately ends upon the jDostero-inferior part of the mesial surface at a 

 point just behind the lower part of the hippocampal fissure. This mode of termination 

 of the rhinal fissiu^e in Myrmecophaga has l)een well figured by Forbes *, and presents 

 a close analogy to the disj)Osition which is rejiresented in Tamandua in this memoir 

 (fig. 10). The rhinal fissure in Tamandua (fig. 8) presents a less acute bend than is the 



Fip 



^lob. ant. 

 y ! area A 



area 6 



^ cerebellum 



; paraflocc. 



bulb ■ olfftpt ■ ' '""> I flocculus 



pulD. oaaot.jj.^gj olfact.; Pjnform.; 



fiss. rhinal. pons Varol. 

 Lateral surface of brain of Tanniitdua titradacff/h(. Nat. size. 



case in the larger Ant-eater, and as a result it approaches much nearer the posterior 

 margin of the hemisphere, but otherwise its disposition closely agrees with that of 



* Op. dt. Proc. Zool t^oc. London, 1882, fij;. 4. 

 SECOND SERIES. — ZOOLOGY, VOL. VII. 41 



