202 OLIGOCHAETA 



species differs from others. The length of the egg-sacs may, however, be a further 

 difference ; MICHAELSEN states that they occupy segments xii-xvi, with a little doubt. 

 The spermathecae are a little further back than is usual in the genus ; they open 

 between segments ix/x ; in having no stalk they differ from the spermatheca of 

 other species. The ovaries also appear to be somewhat unusual in their size ; they 

 reach from septum x/xi to xi/xii, and are only deficient above the oesophagus. In 

 the large size of the ovaries the species resembles M. viridis. 



(5) Moniligaster bahamensis, BEDDARD. 

 M. bahamensis, BEDDAKD, Proc. Zool. Soc. 1892, p. 690. 



Definition. Length, 25 mm., three gizzards in XIII-XV ; septa V/IX thickened ; sperm-sac 



tying entirely in X. Hab. Bahamas. 



This species is mainly interesting on account of the fact that it comes from the 

 New World, and is at present the only member of the family with that origin. It 

 is a rather more slender species than M. barwelli, but otherwise seems to agree fairly 

 closely with it. The apparent differences concern the spermatheca and the penis. 

 In M. barwelli I did not find a protrusible sac connected with the spermathecae or 

 with the spermiducal gland, such as exist in the present species and in M. indicus; 

 but their apparent absence may, after all, be only a question of a less degree of 

 maturity. It is mainly the habitat which leads me to distinguish this species from 

 the other one mentioned. The same remark applies also to M. indicus, though there 

 is here the further difference that there are four gizzards. I imagine that I have 

 made an error in placing the spermathecal pores in a position corresponding to the 

 interval between the dorsal and ventral setae. 



This is the only species in which the structure of the clitellum and of the ripe 

 ova has been seen. The ova are remarkable for the fact that they are filled with 

 yolk spherules, though they are not markedly larger than those of other earthworms ; 

 the structure of the clitellum agrees with that of the aquatic Oligochaeta in consisting 

 of a single row of cells only. These points, however, are in all probability of generic 

 or family importance, and have accordingly been treated of as such. I mention 

 them here as a matter of history. 



(6) Moniligaster indicus, BENHAM. 

 M. indicus, BENHAM, Q. J. M. S., Vol. xxxiv, p. 361. 

 Definition. Length, i^j-^mm.; number of segments, 150 (about); gizzards in XHI-XVI; 



