ZooL.— Vol. II.] RISEN— OLIGOCHMTA. 217 



The sferm-diicts fuse and become invested with a strong 

 muscular covering in XVII. They penetrate the septum 

 separating XVII and XVIII at some little distance from the 

 body-wall, and then bend downwards and penetrate the 

 body-wall immediately under the septum in the interseg- 

 mental groove of XVII/XVIII. The anterior prostate and 

 bundle of penial setae, however, open into the equator of 

 somite XVII, while the posterior prostates and setae open 

 similarly into the equator of XIX. On account of this 

 arrangement the distance between the anterior prostate and 

 the spermiducal pore is only from one-third to one-fourth 

 that between the spermiducal pore and the posterior prostate. 



The anterior -prostate opens immediately behind the 

 penial setae. The muscular part of the prostate is long and 

 strong. The glandular part is much folded, but confined to 

 one somite. The testes and sperm-funnels in X and XI 

 and the ovaries in XIII are normal. 



The body-wall does not contain a row of the sense organs, 

 found in some other species of this genus. 



The following septa are thickened, principally in the 

 dorsal parts : 



V/VI, VI/VII, VII/VIII, VIII/IX, IX/X, X/XI, 



XI/XII, XII/XIII, XIII/XIV, XIV/XV. 



The nephridia are the most complicated of any which I 

 have observed in this genus. There are about eight rows of 

 sacs on either side of the ventral ganglion, but instead of 

 being regular they vary greatly in size and form, some being 

 almost entire, while others are deeply lobed. The different 

 lobes are more connected than, for example, in Benhamia 

 Bolavi, var. papillata. The ventral micronephridium is as 

 usual the most compound. 



The beautiful color of this species is an unusual one in 

 Oligochseta. Beddard in his large monograph mentions 

 that he has seen a species of Benhamia from Trinidad of a 

 bright green color. It is, of course, impossible to say 

 whether Beddard's species is identical with mine, as cir- 

 cumstances did not allow him to describe it. 



