CiiAP. XVII.] THE BRAIN OK QIJADHUMANA. 



291 



sj)oii(liiio; fissures in any Lomur (lio-. 10:3) in which ih(>y 

 arc present. 



The Howler, like the Marmoset and the Squirrel 

 Monkey, is a New World form. The former, in fact, 

 is the larn-cst of the 

 series, and is usually 

 supposed to helong 

 to the highest group 

 of these American 

 Monkeys. lis l)rain, 

 however, is very 

 poorly developed (lig, 

 ]()!)), and, consider- 

 ing its size, possesses 

 very few surface 

 markings. It is re- 

 markahle chiefly for 

 the very small size of 



the Occipital, and the Fm. no.— nram of the Manpabcy (CercopWiecus 



P i-i 1 1 , n aihiopH}, ui)pGr iiHjicct. (Vogt. ) F, Kroiital ; P, P^ric- 



lUU development OI tal; and O. occipital Lobes. L, Orcat Longitudinal 



the Temi)()ral Lobes. ''i««"'*o; H, Kinsurcof Uolando; V, K.xtcmall'onK'n- 



... <Hcular Fisstn-o ; K, Operculum. A, A, Aseending 



In connection with Frontal ;»•, «'^ »:>, Fir.-t, Second, and Thin] Tiers of 



the VerV Sni'lll Oeci- '''"i'^'^^ <^""^*'J"tion.s. I}, n, Ascending Parietal; li\ 



, ' ''-. I''irst and Second Tiers of Parietal Ct)nvolulion«. 



pital Lobes, Flower* «K <I', First and second Tiers of Occipital Cunvoln- 



haS noted an almost ''"I'lilssinn-le no,nc,u.lature f,,r the ('onv..luii..nsis 

 complete abs(niCe of ^'^^t of n. Wagner, excelling that A, an<l H, are 

 ., I^ , ^ _ nanii'd by Idiii Anterior and Posterior Cent i-al < on- 



tlie J^jXternai aJld Jn- v,.liiti„iis. 'Ihougli it is a terniijiology which is })y 



ii'ans \vitiio\it merit, it has not been commonly 



adopted.) 



ternal Perpendicular 



Fissures. 'J'he brain 



of the Howler Monkey is also remarkal)le for the extreme 



backward extension of the Sylvian Fissun^s [v, v), each of 



which almost reacli(>s the upper and inner border of its 



corresponding hemisphere. 



* 'Ti-occcd. of /ioulog. Soc." 18(5 !•, p. '.VA!^), V\. xxix. 



