331 



are not digestive in function. May not their presence be correlated 

 with the very great development of the muscles of the mantle ; these 

 two features being distinctive of this species? If so, should the 

 glands be regarded as excretory? It seems to me there is as much 

 reason for so regarding them, as there is for assigning the same 

 function to the neural gland. I am however unable to appreciate the 

 evidence upon which rests our belief in the renal nature of the neural 

 gland. The neural gland and the cloacal and pharyngeal glands must, 

 for the present, be regarded as organs of unknown function. 



Ill On some Points in the Anatomy of the Nervous 



System of Boltenia Bolteni L. 



Ä. Hie Innervation of the Ciliated Funnel. 



In Boltenia Bolteni there is a nerve which runs from the ganglion 

 to the walls of the ciliated funnel. Among the fibres of this nerve 

 there are found scattered ganglion cells, unipolar, bipolar, tripolar and 

 sometimes multipolar. In my specimens, which were preserved in 

 formalin ^), I am unable to trace the nerve fibres into actual union with 

 individual cells of the ciliated funnel. This could best be done by 

 maceration methods in fresh material and such I have been unable to 

 obtain. 



Referance to the accompanying figure (Fig. 2) will show the re- 

 lations of the structures described. The funnel lies upon the right 

 side of the ganglion instead of anterior to it, as is usually the case. 

 That the nerve innervates the funnel alone is clearly shown by follow- 

 ing out the series of sections from one of which the figure was drawn. 

 The duct of the neural gland runs up from the ciliated funnel on the 

 right side of the ganglion and passes over the dorsal surface of the 

 latter. The proximal ^) part of the ciliated funnel itself and the distal 

 part of the duct receive the innervating fibres. I can not determine 

 whether those fibres, which are distributed to the anterior part of the 

 duct, run on in close connection with the basement membrane to reach 

 the ciliated cells of the funnel. If not, then they must innervate the 

 non-ciliated cells of the anterior part of the duct. 



1) Sections of material preserved in formalin and stained in Mater's 

 hgemalum give very clear pictures of the outlines of ganglion cells and 

 the course of nerve fibres. The distinction thus brought out between the 

 large and the small cells of the ganglion is interesting. Epithelial tissue 

 such as that lining the ciliated funnel or the duct of the gland does not 

 come out well. 



2) With referance to the ganglion. 



22* 



