464 THE BRAIN OF MAMMALS, BY TH. MEYNERT. 



of the projection system. The relation of the crus or inferior pe- 

 duncle of the cerebellum (Kleinhirnstiel oder schenkel processus 

 e cerebello ad medullam, restiform body) to the projection sys- 

 tem is distinguished from that of the two interlacing systems 

 above mentioned by the circumstance that the connecting arm 

 (Bindearm, processus e cerebello ad cerebrum) forms a connec- 

 tion between the cerebral lobes and the cerebellum, which only 

 appears to be interlaced by the projection system ; that the arm 

 of the pons (Briickenarm, processus e cerebello ad pontem) con- 

 ducts portions of the second link of the projection system into 

 the cerebellum, whilst the inferior peduncle of the cerebellum 

 (restiform body) brings an essential addition to the projection 

 system, its fibres passing from the cerebellum to the posterior 

 columns of the spinal cord. The transverse section of the inferior 

 peduncle of the cerebellum breaks up, according to Stilling, 

 into an external and an internal division. In his great work 

 upon the pons Varolii, so suggestive for cerebral anatomy, he 

 names the external division (fig. 257, MFC] 'restiform body' 

 (Strickkorper), a large fasciculus, which descends from the 

 cerebellum at the level of the pons between the origin of the 

 uppermost and the lowermost roots of the facial (fig. 254, Cr ; 

 fig. 255, St). The corpus trapezoides of Mammals, and the 

 stratum zonale, which covers the external surface of the medulla 

 oblongata, and especially the inferior olivary bodies, are formed 

 by the breaking up of the fasciculi of its most superficial 

 layers (figs. 257, 258 ; Z Z). 



The internal division of the inferior peduncle of the cere- 

 bellum emerges from the cerebellum at about the same level of 

 the pons as the corpus restiforme (figs. 254, ZC, and 255, H), 

 and appears on the inner side of the oval transverse section of 

 the latter as a quadrangular area of fine fasciculi (fig. 257, 8 F O). 

 Stilling is incorrect in describing this internal division of the 

 inferior peduncle as the origin of the slender and cuneate 

 columns. For its fasciculi, apparently descending immediately 

 from the cerebellum (figs. 254 and 255), are far weaker, and, 

 with their small transverse sections imbedded in grey matter 

 containing very large nerve corpuscles (fig. 257, S F O), present 

 a structure totally distinct from that of the cuneate and slender 

 columns (fig. 258, 8 F C). It remains separate, and though 



