372 DE. G. ELLIOT SMITH ON 



,fis3. prima 



,.- paraflocc. dors, 

 lob. ant. 



_■■ ••paraflocc. ventr. 



k 



. • , •. pons Varol. 

 flocculua ' ' 

 nerv. V. 



Lateral (riglit) surface of cerebellum of Xcniu-us. Slightly enlarged. 



The fasura prima is a simple arcuate fissure strictly limited to the anterior surface. 

 It limits a simple anterior lobe which is subdivided by a few arcuate fissures (fig. 30). 



The lohus jloccidl is a prominent and much more independent part of the cerebellum 

 than it is in the other Edentates. In other words, it is not packed so closely. 



The paraflocculus^ is divided, as usual, into dorsal and ventral parts (fig. 33). The 

 paraflocculus dovsalis is a narrow worm-like series of simple folia, which caudally become 

 continuous witli tAvo broad grey bands (fig, 33, .r), which arch mesiaUy and then upward to 

 become continuous with the pyramid, which is here a small and insignificant twig of the 

 central lobe. The cephalic extremity of the dorsal paraflocculus becomes serially 

 continuous with the paraflocculus ventralis, which is composed of much deeper and 

 broader folia than tlie dorsal segment (fig. 33). Upon the mesial side of the 

 ventral part of the paraflocculus we find the flattened cak(iA\\.Q flocculus (figs. 30, 32, 

 and 33), which occupies the interval between the medulla oblongata and ventral part of 

 the paraflocculus, and projects lurther backward («. e. in the caudal direction) than the 

 latter. The flocculus is connected to tlxe nodulus {i. e. the foremost part of the posterior 

 lobe) by means of a baud of medullary substance. The posterior lobe is a very simple 

 median band of grey substance which is subdivided into two parts, nodulus and uvula, by 

 a deep transverse fissure, and in addition it is subdivided by three or four shallow furrows 

 (figs. 33 and 31). It is separated from the small '= pyramid " and its lateral connections 

 by a shallow arcuate fissura secunda (fig. 32). 



Practically the w^hole of the dorsal surface of the organ is formed by the central lobe, 

 which has extended forward over the anterior lobe. The lobe appears to have been 

 stretched in this process and the grey matter separated into a median band and two 

 lateral areas, which are separated by regions in which the medullary matter is exposed 

 (fig. 31, y). The median band is subdivided into about ten simple folia by a number of 

 transverse shalloAV furrows. The subdivision of the area cresceiis or lateral part of the 

 central lobe is very imperfect. 



The representative of the area A consists of the simple narrow foHtim which overhangs 

 the anterior lobe (tig. 30). Its lateral parts are quite hidden in iha flssura prima. 

 The area C consists of the obliquely-placed lateral grey band Avhich begins at the lateral 

 extensions of the 2:)yramid (figs. 31 and 33), and extends upward to the antero-lateral 

 corner of the organ. It is subdivided by about ten simple transverse fiu'rows. Wedged 



