586 W. BLAXLAND BENHAM. 



probably are^ related to oue another^ I am of opinion that 

 the "linocyte " is quite an independent cell. 



Still more recently "thread-containing cells'' have been 

 noted by Eisen in certain Oligoclifeta. He uses the term 

 " nematocytes " in describing them — a term which I think is 

 not altogether suitable, in view of the familiar " nematocyst " 

 of the Cnidaria. His account of these " thread-containing 

 cells " is based upon sections^ and this has, I believe, led him 

 to certain erroneous conclusions as to the form and character 

 of the cell and thread. 



In Ocnerodrilus panamaensis he finds such cells, and 

 he states (p. 131) that "the whole cytoplasm is filiform, and 

 takes the shape of a single, continuous, narrow strand, 

 wound regularly, like a coil of rope." ..." The beginning 

 and end of the thread could be clearly seen" (p. 132). 

 " There is no cytoplasm visible either inside or outside the 

 cytoplasmic thread, which does not fill the centre of the cell, 

 there being always a space there." I tliink, from his de- 

 scription and figures (pi. xi, Hg. IIG), that the discrepancy 

 between this account and my own niay be explained by the 

 fact that he examined no fresh material. 



But I cannot accept his suggestion that " the rope may 

 serve to catch bacteria, sperm fragments, or other foreign 

 substance in the lymph." Had he examined the fluid fresh I 

 believe that he would not have hazarded the suggestion. At 

 the same time I am not in a position to form any idea as to 

 the functions of the thread. 



In this paper Eisen also gives some account of other kinds 

 of coelomic corpuscles occuning in various earthworms, but, 

 since this account is founded on observations of preserved 

 material only, I have no occasion to refer to it more 

 specially. 



With regard to the chemical nature of these cell-products, 

 I regret that I have not been able to form any definite con- 

 clusion, owing to my ignorance of micro-chemistry and the 

 lack of available literature dealing with the subject. 



As will be seen in the above notes, I have used the same 



