AND ZOOGKOGRAPHY OF INDIAN OLIGOCH^TA. Ill 



sacs, must therefox-e ripen in the general body-cavity ; and the 

 incompleteness of the septa allows them to become widely 

 distributed, both through the parent animal and the posterior 

 components of the chain. I believe, however, that the observa- 

 tions I have made, only a part of which I record below, show 

 that this is not the case, and that the cells are really produced in 

 all pai"ts of the chain. 



Whether the ovaries also are similarly non-localized I cannot 

 say. I have described the ovaries as definite organs — as cellular 

 aggregates or as hyaline masses of nucleated protoplasm in 

 which cell outlines were not visible, suspended in the ventral 

 part of the body-cavity on fine strands in front of the level of 

 the setfe of segment vi {i. e., about the position where septum 5/6 

 would normall}^ be). The ovaries of C, diaphanits are several 

 times figured by Vejdovsky as definite spherical or pear-shaped 

 masses : they had previously been described by Lankester, and 

 were seen by Yejdovsky also, in C. limncei. Ova are, however, 

 sometimes met with in the hinder animals of a chain of C. orien- 

 talis; in their early stages, moreover, male and female cells are 

 indistinguishable; and it is possible that in some of the examples 

 which I assume below to be the early stages of the male 

 px-odncts, the cells may be young ova. 



Text-fi£fure 1. 



To illustrate sites of production of genital cells in a specimen of 

 Chcetogaster orientals. 



The above figure represents in outline a specimen of Chcetogaster 

 orientalis, in which the process of fission has demarcated eight 

 future individuals, including the anterior one which we may 

 regard as the parent. The first constriction probably appeared 

 between the four anterior and the four posterior components of 

 the chain, and the first break in the chain would subsequently 

 take place here ; the fifth individual was at the time of observa- 

 tion the most completely differentiated (after the most anterior 

 or parent). The figures aiid their reference lines indicate the 

 places where the sexual cells were visible. 



None were seen at any stage of development in the living 

 animal in the front part of the parent, nor were gonads distin- 

 guishable ; subsequently, after staining, examination in cedar oil 

 showed a small morula, of about four cells, ventrally by the side 



