58 Mr. C. R. Narayan Rao on some 
papilla consists of a circular elevated ridge with a central 
nipple, separated from the former by a deep moat all round. 
Occasionally there may be two such nipples on a papilla, 
when it becomes quadrilateral in outline. If, as occasionally 
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 be composed 
of circular muscle-fibres in the outer rim, and in the central 
nipple occur an outermost circular layer and an inner 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 “trench. 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 ine 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 are muscular structures with the outer transverse and 
the inner longitudinal bands studded with the oval ampulli- 
form gland-cells. Lying in between the muscle-bands of 
both sets are to be found branching connecting-tissne fibres, 
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. 
Male orifice in the intersegmental furrow 21/22 nearer to 
seta-line b, 
Opening of the oviduct segment 13 between seta-space aa. 
eluate pores large between dc, 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 
postclitellar 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. 
Others are tender. 
Dorsally the pharyngeal muscles are densely developed, 
arising from the posterior border of septa 4/5-7/8, and 
