1 86 Journal of Comparative Newvlogy and Psychology. 



GREN, nous ne pouvons pourtout pas souscrire a ses deductions 

 theoretiques." 



The theoretical deduction of Holmgren to which Bochenek 

 cannot subscribe is regarding the significance of the canaliculus in 

 Helix. Holmgren holds that the nerve cells are poorly or richly sup- 

 plied with canaliculi according to the functional condition. Bochenek 

 has observed, however, that the canaliculi of Helix are equally de- 

 veloped in winter and in summer ; that is, during the periods of 

 activity and inactivity. He believes, therefore, that they are constant 

 features and are to be explained as an adaptation of a large cell for in- 

 creased absorbing surface. 



The "nouveau detail" which Nelis ('99) calls "I'etat spiremateux" is 

 in the form of a spireme-shaped or much coiled, continuous band. In 

 material hardened in CtILson's fluid or 5^^ formalin and stained in 

 Heidenhaix's iron haematoxylin and eosin or erythrosin these bands 

 appear uncolored and amorphous, and marked off from the colored 

 ground substance by regular, parallel lines. The position of the 

 spireme varies in position and extent in different cells. It may lie near 

 the periphery of the cell, near the center or in close relation to the 

 nucleus. In some cases one of its borders is indistinguishable from 

 the nuclear membrane ; although the author considers that the two 

 elements do not in reality coincide. 



Nelis finds the spireme in the plexiform ganglion of the dog, and, 

 less conspicuously, in the superior cervical ganglion. It is present in 

 the pyramidal cells of the cerebral cortex and in the spinal ganglion 

 cells also. He considers that this is a normal structure, but that under 

 certain pathological conditions it may become much more extensively 

 developed and more easily demonstrated. As to its significance, 

 Nelis is undecided, but he is inclined to interpret it as a protoplasmic 

 element of the cell. 



De Buck and de Moor ('99), in a work upon the lesion of the 

 nerve cells accompanying experimental tetanus in the guinea pig, find 

 a system of vacuoles which they identify with the spireme of Nelis. 

 These vacuoles may approach very near the border of the cell, but are 

 always separated from it by a thin layer of protoplasm. Van Gehuch- 

 TEN and Nelis ('00) have observed the structure also under pathological 

 conditions and conclude that it is accentuated by arsenic poisoning, 

 tetanus, etc. 



Among these various descriptions of intracellular vessels it is quite 

 easy to identify the type described by Kolster with the canaliculus of 

 Holmgren, by assuming that Kolster has failed to demonstrate the 



