MR. FLOWER ON THE BRAIN OF THE JAVAN LORIS. 107 



the Carnivora in structure. The flocculus consists of four lamellse, attached by a very 

 narrow pedicle, and lodged in a fossa in the temporal bone, as in the other Quadrumana. 



Comparison of the Brain of Stenops with that of Lemur. 



The brain at present under consideration presents the same general characters, both 

 of form and disposition of the surface-markings, as that oi Lemur nigrifrons (figs. 5, 6, 

 and 7). The principal differences that may be observed between them are: — In Lemur 

 the hemispheres are rather rounder and fuller, though the anterior lobes are more com- 

 pressed. The temporal lobe is rather more developed. In the sulci of the outer face, 

 in Lemur, the Sylvian fissure is deeper, especially at its anterior or lower part, and con- 

 ceals a small but distinctly marked insula or median lobe; it does not extend so far 

 upwards and backwards ; and there is a sulcus (" angular") running lengthwise on the 

 hemisphere between the upper end of the Sylvian fissure and the great longitudinal 

 fissure, no trace of which exists in Stenops. In the arrangement of the sulci of the inner 

 face the two brains closely resemble each other. 



Comparison of the Brains of Stenops and Lemur with those of the higher Quadrumana. 



As has been so clearly demonstrated by M. Gratiolet in his beautifully illustrated 

 memoir before referred to, a certain type, both of general conformation and of surface- 

 markings, pervades the brain of all the Primates, from Man to the Marmoset. From 

 this type M. Gratiolet excludes the Strepsirhine Quadrumana, associating them with 

 the Insectivora, in a division of Mammalia whose cerebral organization he considers to 

 be quite distinct ; but as his promised work upon this group has not yet seen the light, 

 we are but imperfectly informed of the grounds upon which this conclusion is based. 



In general form the Lemurine brain certainly departs considerably from the form of 

 what may be called the Primatial type of brain, and approaches more nearly to that of 

 the Carnivora. This is particularly apparent in the shortness of the posterior lobes 

 of the cerebrum, which in the two higher families of Quadrumana (I believe, without 

 exception) completely cover, and in most cases project beyond, the cerebellum'. But 

 it must be observed that there is a considerable difference iu this respect among the 

 members of those families, and that this difference follows no regular gradation, and 

 appears not to be correlated with any other structural characteristics. And it is 

 especially remarkable that, in the development of the posterior lobes, there is no 

 approximation to the Lemurine shorl-hemisphered brain in those Monkeys which are 

 commonly supposed to approach this family in other respects, viz. the lower members 

 of the Platyrhine group. 



' Since this was written, an exception has been described in the genus Hylobates. See Natural History 

 Review, April 1863, p. 279. 



