150 Zoological Society : — 



March 11, 1862.— Dr. J. E. Gray, F.R.S., V.P., in the Chair. 



Mr. W. H. Flower, F.R.C.S., F.L.S., Conservator of the Museum 

 of the Royal College of Surgeons, read a memoir on the Brain of 

 the Javan Loris {Stenops jav aniens) . 



The subject of this communication was an adult female, which died 

 in the Zoological Society's Gardens in January, 1862. In the exa- 

 mination of the brain every care had been taken to preserve the natural 

 configuration of the different portions of the organ ; the drawing of 

 the upper surface had been made before its removal from the cranial 

 cavity, and the other drawings, descriptions, and measurements were 

 checked by comparison with a cast of the interior of the skull. The 

 value of the descriptions and figures of the brain of Stenops already 

 published had been much diminished by inattention to such precau- 

 tions ; and they had also had the disadvantage of being made before 

 the researches of Gratiolet had thrown light upon the arrangement 

 of the convolutions on the cerebral hemispheres of the higher Qua- 

 drumana. A new description, which may serve as a standard of 

 comparison in studying the cerebral anatomy of allied forms, seemed 

 therefore to be called for. 



The following is an abstract of Mr. Flower's remarks : — 



" When seen in situ, the two hemispheres present together an oval 

 figure, 1*3 inch in length, and 1*05 inch across the broadest part, 

 which is situated at the junction of the middle and posterior third of 

 the long axis. From this point the oval gradually narrows to rather 

 a sharp apex in front. There is no appearance of that want of 

 symmetry, both of size and form, in the two hemispheres, described 

 and figured by Vrolik. Projecting anteriorly to the extent of ^^ inch 

 beyond the cerebral hemispheres are the olfactory lobes, of consider- 

 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, di- 

 stinctly 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, calloso-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 



