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A. L. TREA DWELL. 



break in the dorsal wall is apparently due to the latter. The 

 intestine, ////., Fig. I, shows in the section as a minute tube, in 

 whose walls no definite cellular structure could be seen. In 

 many sections I could find no trace of the intestine. While this 

 may possibly be due to the technique, I do not think that they 

 could have dropped out of so many sections, and believe that 

 there was an actual disappearance. Such a condition with 

 respect to the intestine is not unusual among annelids at the 

 breeding season. 



Ventrally is the section of the nerve cord, and on the right a 

 part of the parapodium is seen. The parapodial muscle bands 

 are very feebly developed. 



As shown in Fig. I large numbers of ova are present in the 

 body cavity. These fill the whole cavity, extending forward into 

 the head, so that, as is shown in Fig. 5 a section through the 



FIG. 2. Section through posterior region of same individual as in Fig. i. X 2 4- 

 sp, spermatozoa adhering to surface, other letters as before. 



eye shows at the same time an ovum, contained in a cavity 

 between the muscles of the head. That this condition is usual 

 can be seen by careful surface examination of the entire annelid. 

 The ova appear to have a very dense outer layer with vacuolated 

 interior containing a nucleus. As it is impossible to tell how much 

 of this apparent structure is an artefact, I have represented it only 

 in a very diagrammatic fashion in Fig. I , while in Figs. 2 and 5 

 I have drawn merely the outlines of the ova. 



Scattered among the ova are many sections of connective tissue 



