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no isolated nerve cells I can explain those described by Lenhoss^k 

 only on the assumption that his nerve cells are the sense cells of the 

 epidermal sense organs described by earlier writers. This assumption 

 will, I believe, be found to be fully warranted by the facts detailed in 

 my final paper. 



The silver stain further shows that the epidermis of Lumbricus 

 contains, in addition to the fibres already described, numerous intra- 

 epidermal nerve fibres which extend from a subepidermal net- 

 work and pass between the cells of the epidermis where they end 

 free. The subepidermal net-work is formed from nerve fibres which 

 have their origin in cells of the central nervous system and which do 

 not appear to be connected with any other cells. 



By means of preparations made by removing the cuticula of an 

 entire worm and drying it upon glass slips I have been able to make 

 an accurate study of the distribution of the sense organs. The portion 

 of cuticula covering each organ is elevated and perforated by nume- 

 rous fine canals through which the sense hairs protrude. There are 

 thus formed numerous "pore-islands" which stand out with great 

 clearness in such preparations as I have mentioned. It is thus pos- 

 sible to study the distribution of the sense organs with minute accu- 

 racy. They occur in great numbers on every part of every metamere 

 and in the buccal cavity. They are more numerous on the cephalic 

 and caudal metameres than in the middle of the body. The organs 

 of each metamere are not uniformly distributed nor are the organs 

 of uniform size. Each metamere is encircled by two narrow but well 

 marked zones of larger organs, one at its cephalic end (cephalic) and 

 one near its middle (median), and there is further a compact group 

 of smaller organs about each nephridial opening. 



The more important results of my work may be thus broadly 

 stated : 



1) There are numerous multicellular sense organs in the epidermis 

 of Lumbricus. 



2) The sense cells of these organs give rise to nerve fibres. 



3) The nerve fibres have free endings in the central nervous 

 system. 



4) The epidermis contains numerous free endings of nerve fibres 

 which arise from cells in the central nervous system. 



5) The sense organs are distributed in a definite manner. 



My results as stated under 1 and 4 are directly opposed to 

 those of Lenhossek. If the ganglion cells described by Lenhossek 

 are, as I believe, identical with the sense cells described by me in the 



