1908.] W. MiQKA'S.'i.S'E'^ : Oligochœta of the Indian Empire and Ceylon. 137 



sexual organs and their pores generally, agrees with the genus Drawida, MICHLSN.' 

 I committed an error when I wrote "Vielleicht steht sie (z.ß., the genus Moniligaster) 

 zu Eupoly gaster in etwas näherer Beziehung."^ The two genexâ Moniligaster and 

 Drawida form a narrow group, which doubtless has a common origin from the 

 most archaic genus of this family, i.e., from the genus Desmogaster. Probably Monili- 

 gaster is a direct descendant of Drawida. It might even be justifiable to unite these 

 two genera, to include the genus Drawida without restriction in a genus Moniligaster 

 sensu lato, or to regard Moniligaster sensu stricto and Drawida as sub-genera of a genus 

 Moniligaster sensu lato. The only essential point of difference between these 

 two genera is based upon the structure of the s'pQ.im.2it\\.QQ2&, Moniligaster {sensu stricto) 

 possessing at each side a pair of much-branched glandular tubes opening into the mus- 

 cular atrial cavity of the spermatheca and Drawida being destitute of such glands. But 

 these organs are in a manner foreshadowed in some species of Drawida. In D. robusta 

 (BOURNE) and its sub-species we find a bifurcated muscular atrial cavity at the distal 

 end of the spermatheca, and this atrial cavity seems to correspond exactly with the 

 atrial cavity which bears in Moniligaster the branched tubular glands. As we possess 

 a very careful and detailed description and figure of this organ in BENHAM's paper 

 upon Moniligaster indicus'^ [=Drawida robusta (BOURNE) sub-sp. indica (BENHAM)], 

 I am able to make an exact comparison between Moniligaster and the adjacent species 

 of Drawida in respect to this organ. I may amplify it into a general discussion upon 

 the spermatheca of the Moniligastridce and the morphological and functional signifi- 

 cance of its different parts. 



In all the Moniligastridce each spermathecal apparatus has a thin-walled pear- or 

 sack-shaped pouch lying in the segment just behind the intersegmental furrow of the 

 spermathecal pore, and opening through a thin, much bent or coiled duct' In all 

 the species of Desmogaster and Eupoly gaster and in one species of Drawida this long- 

 stalked pouch, opening directly to the exterior, represents the whole spermathecal 

 apparatus. In some species of Drawida the distal end of the duct of this pouch widens 

 and is transformed into a muscular coat. In other species of this genus this widened 

 muscular distal end grows into a real muscular atrial chamber, which further on enlarges 

 at one side to form a separate blind sac, depending into the second segment, or, in 

 the species D. robusta and its sub-species, at two sides, forming two outgrowths, one 

 depending into the seventh segment, the other into the eighth segment, the two 

 outgrowths being separated by the septum 7-8, and the duct of the pouch entering 

 the atrial chamber at the angle between these two outgrowths. The structure found 

 in the species of Moniligaster may be compared with this structure in Drawida 

 robusta. The two outgrowths of the atrial cavity in the latter species are continued 

 in Moniligaster each into a large gland, consisting of a large, much-branched tube, 

 the branches and twigs of which are packed together and enveloped in a peritoneal 



MV.MlCHAElvSEN,01igochœta; in Tierreich, Lief. 10, p. 114. ■ ■ " '' • 



''' W. MICHAEIySEN, Die geographische Verbreitung der Oligochœten, Berlin, 1903, p. 65. 

 " W. B. BENHAM, Description of a New Species of Moniligaster from India ; in Quart. Journ. 

 Micr. Sei., N. S., vol. xxxiv, pp. 362—382 ; pi. xxxii, figs, i — 5, pi. xxxiii, figs. 8 — 15. 



