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



pedicle springing from the middle of its anterior margin to the infundibulum, and 

 divided by a transverse groove into two lobes, of which the posterior is much the 

 smaller. 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 medulla oblongata is broad and flat anteriorly, the median groove distinct, 

 its other divisions but faintly indicated. A slight longitudinal groove marks the outer 

 boundary of the pyramidal bodies ; but the olivary bodies make no projection on the 

 surface, and the corpora trapezoidea are not well defined. The nerves appear all to rise 

 in the usual situations. 



On separating the hemispheres above, while still in situ, the corpus callosum was 

 seen to cover half of the anterior pair of the corpora quadrigemina. Of these bodies the 

 anterior are the largest ; they are flat and rounded in outline, narrower before than 

 behind ; the posterior are small, but very prominent. The corpora geniculata are well 

 marked ; the pineal gland small. On dividing the corpus callosum, the posterior part 

 of the fornix was seen to be extremely broad, covering the optic thalami, and forming a 

 broad, wide lamina (corpus fimbriatum) descending into each middle cornu of the 

 ventricle. The hippocampus major is of moderate size. Although every care was 

 taken to ascertain the extent to which the ventricular cavity extended into the posterior 

 lobe, I was not able to do so satisfactorily : so readily do the layers of brain-substance 

 separate in this direction, following exactly the curve of the bottom of the calcarine 

 fissui-e, that it is difficult to distinguish an artificially formed from a natural cavity ; 

 but, as I have elsewhere shown, the extent to which the walls of tliis portion of the 

 ventricular cavity are adherent is of no anatomical or physiological importance, and 

 varies even in the same species ; while, on the other hand, it is of consequence that, if 

 the homologies of the calcarine sulcus as traced from Man through the Quadrumanous 

 series to Stenops, Lemur, and Galago are true, the portion of cerebral grey matter 

 answering to that forming the so-termed " hippocampus minor " of the human subject, 

 only of proportions corresponding to the greater relative depth of the calcarine sulcus, 

 must exist in the brains of all these animals'. 



When a horizontal section had been made of the hemisphere, the length of the 

 antero-median portion, measured to the posterior edge of the hippocampus major, was 

 0-9 inch, and that of the posterior portion 04 inch, giving a proportion of 100 to 44, — 

 being a shorter posterior lobe than in any of the true Apes that I have measured 

 [Hylohates excepted], and longer than in any of the inferior Mammalia. 



The cerebellum is 0'7 inch in breadth, and 0'4 inch in length. The upper surface is 

 flat, rising but slightly in the median line, the superior vermiform process being much 

 less distinctly marked than in Lemur, but forming a projection instead of a notch (as 

 in the human subject) in the posterior border when seen from above. The lateral lobes 

 are of moderate size, and more resemble those of the higher Quadrumana than those of 

 ' "On the Posterior Lobes of the Cerebrum of the Quadrumana," Phil. Trans. 1862, pt. 1, p. 185. 



