204 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



33. The conflicting evidence upon the development of the nephridium 

 in Annelids makes it impossible closely to homologize this structure and 

 the antennal glands of Macrura. The endsac may be homologous with 

 the nephrostome of the nephridium of Annelids together with (or) none, 

 (b) a part, or (c) all of the remainder of the organ, depending upon 

 which is the correct view in regard to the development of the nephridium 

 in Annelids. 



34. The nephridium of Annelids is probably represented in Crustacea 

 in the second (antennal) segment by the antennal gland of Malacostraca ; 

 in the fifth (second maxillary) segment by the shell gland of Entomos- 

 traca and some Malacostraca ; in the sixth (first maxillipedal) segment 

 of some Malacostraca by the " Segmentalorgan " of Lebedinski ; it is 

 possibly represented in the fourth (first maxillary) segment by the ex- 

 cretory organ described by Boutchinsky, and in the sixth to thirteenth 

 (maxillipedal and pereiopodal) segments in part by the branchial glands, 

 and in part (in the eleventh and thirteenth segments^ by the genital 

 ducts. 



Mat 1, 1898. 



