VOL. II.] Anatomical Notes on Sittroa Alpestris. 327 



uous organs in the body, filling the largest part of the somite 

 (Fig. i). There can be no doubt as to the true nature of th 

 bodies, as they are full of spermatophores and spermatozoa in 

 all stages of development. These bodies were described by 

 Vejdovsk}^ as testes. '=^ 



But at a later date this learned investigator supposed that he had 

 made an error in ascribing to these bodies the nature of testes, and 

 suggested that their 'nature is only that of a seminal vesicle, and 

 that the true testes, as well as the ovaries, are to be found in some 

 of the somites anterior to the efferent ducts and the spermaducal 

 pores.f 



I shared this opinion when I described Eclipidrihis frigidiis. A 

 larger material of this worm as well as of Sutroa enables me to take 

 a different view of these organs. Thus in Sutroa rostrata the 

 spermathecal porus is found in VIII. In somite IX we find two 

 large bodies similar to the albumen glands in Sutroa rostrata, while 

 in somite X are f^und the two testes proper. Undoubtedly the 

 ovaries must be looked for in the somites posterior to the sperm- 

 sacs, possibly in XXXIL In both species ol Sutroa the sperm- 

 sacs cover the atrium and prostate to such an extent that it is diffi- 

 cult to separate them and clearly define one from the other. But 

 the sperm-sacs are not really connected with the prostate, as can be 

 seen in the anterior segments of this organ where the prostate lies 

 free and is not covered by the sperm-sacs. The real testes in Sutroa 

 rostrata are smaller and not lobed, whereas in Sutroa alpestris the 



r 



testes are large and deeply and repeatedly lobed. (Figs, i and 15.) 

 The sperm-sacs or testes in Rhynchelmis, as well as In Sutroa, 

 extend thus through several (6) somites, occupying more or less 

 segments, as the worm is older or younger. 



These sperm -sacs contain spermatophores in all stages of develop- 

 ment. In the posterior part of the sperm-sac, which also is the 

 largest (Fig. i), the spermatophores are the most advanced in de- 

 velopment. Thus it is important to notice that the spermatophores 

 develop directly in the sperm-sacs, and that they are not formed 

 afterwards by an aggregation of spermatozoa. I cannot agree with 

 Vejdovsky, that the formation of the spermatophore is quite as simple 



*Vejdovsky on Rhynchelmis, loc. cit. Taf. xxii, fig. 6, 



t Vejdovsky, System and Morphologic der Oligochanen, Prague, 18S4, pag. 57, 



