104 MR. W. H. FLOWER ON THE JAVAN LORIS. [Mar. 11, 



able vertical depth, but compressed laterally, and pointed in front. 

 Projecting posteriorly is a very narrow edge of the cerebellum, most 

 visible in the middle line, both on account of its own greater promi- 

 nence at this part, and because the widening out of the termination 

 of the great longitudinal fissure of the cerebrum allows more of its 

 upper surface to be seen. When seen from one side, the upper con- 

 tour of the brain forms a low, flattened arch, the greatest point of 

 elevation being a little way behind the centre. The anterior or 

 frontal lobe is much depressed, and excavated below to make room 

 for the orbital plates of the frontal bone. The temporal lobes, dis- 

 tinctly marked off from the last by the Sylvian fissure, are full and 

 make a considerable projection downwards and forwards. The occi- 

 pital lobes are short and of little vertical depth, being hollowed 

 below for the cerebellum, the greater part of which body they cover. 

 The sulci of the cerebral hemispheres, though few, are well marked 

 and tolerably symmetrical. A particular description of their arrange- 

 ment is given in the paper. The principal sulci correspond with 

 those which in the higher Quadrumana have been named Sylvian, 

 antero-temporal, cailoso-marginal, calcarine, and dentate. 



" On the inferior surface of the brain, the olfactory lobes in their 

 anterior half are seen to be compressed, and of equal width almost 

 to their termination ; posteriorly they become flat, and widen out to 

 their attachment to the under surface of the anterior lobe. The 

 fissure of Sylvius divides them from the temporal lobe. The orbital 

 surface of the hemisphere, as seen on each side of the olfactory lobes, 

 is hollowed out, and presents a simple longitudinal sulcus. The 

 optic nerves are small for the size of the brain ; behind them is a 

 prominent, round, whitish mass filling up the greater part of the 

 interpeduncular space, in which the corpora albicantia are not clearly 

 distinguished from the tuber cinereum. The crura cerebri are of 

 moderate size. The pons Varolii is not much elevated ; it is distinctly 

 marked off in front, but very indefinitely separated from the medulla 

 behind. The last-named body is broad and flat anteriorly, the 

 median groove distinct, its other divisions but faintly indicated. 

 The nerves appear all to rise in the situations usual in this group of 

 animals. 



"The corpus callosum is 0'65 inch long, and covers half of the 

 anterior pair of the corpora quadrigemina. Of these bodies the an- 

 terior are the largest, they are flat and rounded in outline ; the pos- 

 terior are small, but very prominent. The posterior part of the 

 fornix is very broad, covering the optic thalami, and forming a wide 

 lamina (corpus fimbriatum) descending into the middle corner of the 

 ventricle. The hippocampus major is of moderate size. With all 

 the care taken, it was not possible to ascertain satisfactorily the extent 

 to which the ventricular cavity passed into the posterior lobe ; but 

 this is a circumstance of very little importance, and varies greatly 

 even in the same species of Quadrumana. On the other hand, it is 

 of considerable anatomical and physiological consequence that the 

 portion of grey matter homologous to that forming the so-termed 

 ' hippocampus minor' of the human subject, only of proportions 



