58 Mr. C R. Narayan Rao on some 



papilla consists of a cirmlar elevated ricljje with a ecntral 

 nipple, separated from the former by a deep moat all round. 

 Oecasionally there may l)e two sueh nip|)les on a papilla, 

 when it becomes qnadrilateral in outline. U\ as occasioually 

 happens, the papillary somites should bear secondary 

 annular ridges, these latter become conspicuous bars con- 

 necting the three rows of tubercles on the somite, which in 

 cross-section is more like a segment of a circle. In sectional 

 preparations (fig. 4, A), the tubercle is seen to he composed 

 of circnlar muscle-fil)re8 in the outer rim, and in the central 

 nipple occur an outermost circular layer and an iuner band 

 of vertical muscles, which converge towards the apex in an 

 oblique manner from all round the neighbourhood of the 

 outer rim. There are no sensory cells of any kind on 

 them, and only a few large oval glandular cells, occurring 

 chiefly in the treuch. Judged from their structure, there 

 can be little doubt that the tubercles act as organs of 

 adhesion in a sexual act, and when we consider the fact 

 that the surroundings in which these worms live are likely 

 to be suddenly inundated, the need for suctorial organs of 

 some sort becomes all the greater. The lateral clitellar 

 wings arc muscular structures with the outer transverse and 

 the inner longitudinal bands studded with the oval ampulli- 

 form gland-cells. Lying in betwceu the muscle-bands of 

 both sets are to be found branching connecting-tissue fibi'cs, 

 which enable these flaps of skin to be stretched out fairly 

 widely. 



No genital pores can be made out, except in sections. 

 Spermathecal apertures occur in intersegmental furrows, 

 ^lale orifice in the intersegmental furrow 21/22 nearer to 

 seta-line b. 



Opening of the oviduct segment 13 between seta-space aa. 

 Nephridial pores large between be, very well marked behind 

 segment 12, and inconspicuous anteriorly. 



Colour. — In spirit-specimens the colour is a dark grey, 

 with occasionally traces of orange on the anterior part of 

 the body. In the live specimens the greater part of the 

 j)Ostclitellar region is yellow with a dark, broad, dorsal and 

 frequently ventral band. The whole clitellar portion is 

 grey or even white, and the body in front is yellowish red. 



Internal organisation. — The first recognisable septum 3/4 

 is composed of a few muscle-bands only, 4/5 better developed. 

 Septum 5/6 is only slightly and 6/7-14/15 very thick. 

 Otliers are tender. 



Dorsally the pharyngeal muscles are densely developed, 

 arising from the posterior border of septa 4/5-7/8, and 



