62 Ikfr. C. R. Narayau Rao on some 



they resemble closely except in size. In view of the ahsencc 

 of the dorsal pores, and consecjuentiy tlie conii)letc shutting 

 otf of the segmental cavities from the ontside world, it is 

 only reasonable to associate in some sort of manner the 

 uniform occurrence of the bubbles with the cell-aggregates 

 of the secondary chambers. In other words, the ventral 

 portion of the Crt;lomic cavity perhaps acts as a hydrostatic 

 chamber, which in worms whose environment is susceptible 

 of being frequently inundated by suddeu floods must be 

 extremely of a useful character. 



Glyphidrilus elegans, sp. n. 



External characters. — The largest specimens measure 

 13G mm. ; number of segments 18G-270; circumference of 

 body about segments 9-14 3^ mm. where the body is round; 

 from segments 18-24 5 mm. across the body where it is 

 Hat ; between the inner borders of the clitellar wing 5-5 mm., 

 liere the body is thick and flat. Behind the body gradually 

 narrows and is foui'-cornered, with the dorsal, ventral, and 

 lateral canals. Sometimes the dorsal depression may extend 

 forward up to segment 13; segments 7-13 are broad and 

 tliose behiud are extremely short, nearly half or less than 

 half of the anterior ones. Segments in the posterior part 

 of the body only gradually become short and can be counted 

 up to the anus, which is dorsal and terminal. The anterior 

 preclitellar segments have secondary annular ridges aud 

 grooves. 



Prostomium zygolobous. 



Dorsal pores absent. Nephridial pores from behind 

 segment 12 in seta-space be. 



In segments 24-32 aa = 2\ab and = 2a6 both in front 

 and behind this region, and gradually becoming less than 2ab 

 both ways ; aa is greater than be or tld ; ab = cd. 



The clitellum is marked from segments 14-35, 48 

 ( = 22-35). 



The genital markings are three, or only two rows of 

 puberty-tubercles. The median, when present, commences 

 from segments 12-13, and quite variable in number (7, 12), 

 and the laterals, which are uniform in their occurrence, 

 begin on segment 13 extending up to segment 24. Behind 

 the puberty-wiiig, the lateral series may be continued on 

 segments 32-36 on one or both sides and the median ones 

 on segments 41—42. Each of these tubercles, which in 

 point of disposition and microscopical structure resembles 

 the foregoing sjiecies, differs from them in a marked manner 

 by their oval or transversely elongated shape. The secondary 

 annular ridges fjom si-gments 18, 22 are very strongly 



1 



