Si:XUAL PHASE IN INDIAN NAIDID/E. 



463 



separated off as a sort of cocoon, while the hinder part of the 

 animal lived for some time, hut was nnahle to regenerate and 

 ultimately died. It appears, then, that death ensues after the 

 full attainment of the sexual phase, and the cocoon is probably 

 the whole anterior region of the worm which has been separated 

 .off. 



Branchiodrilus hortensis Stephenson. 



Many examples of this species were collected during the last 

 two weeks of Octol)er and the first two weeks of November, from 

 the mud at the bottom of a pond at Sikandra ; and of these 

 nine were found to possess fully developed sexual organs (text- 

 fig. 3). 



Text-figure 3. 



Ginnttil region of BraiicJn'odrilns hortensis. The atria lie one on each side of the 

 sperm-sac, and the vas deferens is seen running internal to the atrium of 

 its side ; the funnel lies far behind in the sperm-sac. Pr., prostate ; the 

 remaining letters as before. X ca. 125. 



The clitellum occupies segments v.-viii. ; it is opaque white in 

 the living animal. It is about "05 mm. thick; the cells have a 

 coarse reticular structure, the meshes of the network being clear 

 spaces ; the nuclei are indistinct. The clitellum is absent 

 between the spermathecal openings an<l on the ventral surface in 

 the anterior portion of segment v. It is formed after all the 

 other sexual organs have been developed. 



The testes had disappeared in all the specimens examined. 



The sperm-sac may reach as far ])ack as segment xix. or xx., 

 in two cases to xxvi. ; usually it extended to xviii. 



The male funnels are within the sperm-sac, some distance 

 behind its mouth, and here they nearly till up the available space. 

 Their lips are everted, and their outer margin is attached to the 

 wall of the sperm-sac. The width of the funnel is 90 /x ; its cells 

 are high and ciliated, with nuclei at their base. The cells and 

 cilia of the upper lip seem to be taller than those of the lower. 



The vas deferens is 30 in diameter ; it is a fairly long tube, 

 about '2 mm. in length, and consists of two parts, a posterior 



