Herrick, Pathology of General Paralysis. 157 



(Hirt's Diseases of the Brain, p. 197). Ectad of the internal 

 capsule, which evinces no alteration that can be detected by 

 the means here employed, is the head of the caudatum, consist- 

 ing of a stroma of densely nucleated matter and sporadic fibre 

 bundles. There is almost absolutely no alteration in the sub- 

 stance of either caudatum or lenticulare at this level. We may 

 add that the present tendency to attribute important psychical 

 functions to the striatum has as little anatomical foundation as 

 psychological significance. By far the largest part of the striata 

 is composed of sporadic bundles from the capsule. The vessels 

 of the striatum are nearly normal. The lesion is decidedly cor- 

 tical. A series of sections through the peduncular region is of 

 special interest as showing that in this segment the degenera- 

 tion is limited to the motor projection system. The cells of 

 the tectum and niduli of the cephalic quadrigemina, as well as 

 of the ruber, are scarcely modified at all. The nidulus of the 

 oculo-motor is quite unaffected. There are slight changes in the 

 pulvinar and other niduli of the thalamus, but when we turn to 

 the vicinity of the motor peduncle fibres we encounter most con- 

 spicuous evidence ot degeneration. The large and complicated 

 nidulus niger, including the most remarkable cells of the mesen- 

 cephalon is almost completely altered. These cells, which hug 

 the ental margin of the peduncles and form the boundary be- 

 tween tegmentum and crusta are not only of enormous size, but 

 by reason of the great extent of their processes they stand out 

 among the elements of the brain. In a series of papers^ the au- 

 thor has endeavored to follow the homologies of the nidulus 

 thrbughout the veretebrate phylum. It has proven possible to 

 trace the relation between the pecular cells, which are not easily 

 mistaken for any other cells in the brain, from fishes to mammals. 

 The development of the nidulus niger or Soemmering's nidulus 

 stands in close ratio with that of the cerebellum. In fishes the 

 ventral peduncular fibres, which can hardly be other than the 



^Contributions to the Morphology of the Brain of Bony Fishes, Journ. 

 Comp. Neurology, Vol. II. Notes upon the Histology of the Central Nervous 

 System of Vertebrates. Festschrift zum siebenzigsten Geburtstags Lenckarf s; 

 Anat. Anteiger^ VII, 13, 14. 



