30 Journal of Comparative Neurology. 



around the median side of the palp ganglion of its own side 

 and appears to enter a mass of large ganglion cells just caudad 

 of the latter. 



All the nerves containing the central processes of the dif- 

 fuse sense-organs found in the various lobes of a parapodium 

 join into a main trunk which passes into the parapodial ganglion 

 situated near the base of each ventral parapodial cirrus. From 

 this ganglion a nerve passes directly to the ventral nerve cord 

 of its own metamere. 



D. Ultimate Endings of the Central Processes. 



From the foregoing description, it is seen that the 

 central processes or nerve-fibers from the diffuse sense or- 

 gans situated in the various appendages of the body may either 

 be traced directly into the central nervous system or into per- 

 ipheral ganglia connected with the central nervous system. 

 The central nerve-fibers from the organs found in the body 

 epidermis without doubt also pass into the central nervous sys- 

 tem, but this cannot be so readily demonstrated. The final 

 termination of all these central processes is a question which 

 cannot be definitely decided by means of my present material. 



In my methylene blue preparations, large numbers of the 

 ganglion cells in the ventral nerve-cord, in the brain, and in the 

 ganglia at the base of the parapodia and the cephalic cirri are 

 surrounded by apparent pericellular ne?ve-baskets. I use the 

 term apparent advisedly for I feel yet undecided whether all or 

 any of these structures are normal. Most of the ganglia in 

 which these baskets are found probably receive other centripe- 

 tal fibers besides those from the diffuse sense-organs. But in 

 my preparations the central processes of these organs are the 

 only centripetal fibers which are stained. Moreover, two of the 

 ganglia which show these apparent baskets — the two palp gang- 

 lia in the anterior part of the brain — receive, so far as I can 

 see, only centripetal fibers from the diffuse sense-organs. 

 Therefore, if proved normal, these pericellular baskets would 

 be without doubt the final terminations of the central processes 

 from the diffuse sense-organs. 



