50 Memoirs of the Indian Museum. [VOLE 
External characters —Length of largest specimen 195 mm., diameter 7 mm. Dor- 
sally the colour is a slaty grey, with a pink tinge posteriorly, ventrally a lighter grey; 
the lateral region in the anterior portion of the animal appears thickened, the inter- 
sezmental furrows being deeper as they cross this lateral region than above or below 
it; this lateral region is in tint the lightest portion of the body. 
Segments 183—186 ; posterior end tapers rapidly, the segments being very small. 
The prostomium is small and zygolobous. 
With the higher powers of the dissecting binocular rings of minute ab light 
in colour, are seen on the anterior or on most of the segments of the body. These 
papillae resemble those caused by extremely numerous and minute perichaetine setae, 
and are possibly of the nature of sense organs. 
I could not in all cases be certain as to the segment on which the setae begin. 
In one specimen the ventral bundles began in ii, the lateral apparently in iv; in 
another both bundles began from iii, and in a third from iv, though lateral setae were 
doubtfully present in iii. 
A few of the setae were examined microscopically. A seta from Sarnen! vill is 
shown in fig. 6; its length is 52 mm., breadth at nodulus ‘041 mm. ; the basal portion 
is seen to be very stout, the free end being curved and pointed. ‘The distal fifth or 
thereabouts shows a number of very fine sculpturings ; under the oil immersion lens 
these appear to be angular, with point directed backwards (basalwards); they are 
possibly spines, though they cannot be seen to project from the sides of the shaft. A 
second seta from the same segment was considerably thicker at the nodulus (054 mm.). 
A seta from a few segments further back showed the thickening of the base in a more 
exaggerated form; but this curious deformation was not present in a seta taken some 
distance behind the genital region. The sculpturing appears to be constant. It 
should be added that probably all the setae examined were of the nature of reserve 
setae, which had not yet come to project freely on the surface. 
here was no clitellum in any of the specimens, notwithstanding that dissents 
showed them to be sexually mature. 
The nephridiopores in the anterior part of the body are in the line cd ; in the middle 
and posterior regions they are mostly lateral, in cd, but occasionally centrale in ab. 
Internal anatomy.—Septum 4/5 is distinct and somewhat thickened. Septa 10/11 
and 11/12 are fused in such a manner as to form a ring-like ovarian chamber above the 
alimentary canal. 
The gizzards vary; the most posterior is the largest, and the anterior ones are 
successively smaller. It is really scarcely correct to speak of separate gizzards; there 
are only slight segmental constrictions in a continuous hard muscular tube. One 
might reckon six gizzards, in xvi to xxi, in the specimen first dissected, though the 
anterior one or two were weaker than the rest; the oesophagus was still firmer than 
normal and somewhat thickened in xv. In a second, six were counted, in xiv to xix, 
the first being less firm than the rest. Ina third, belonging to the second batch of 
specimens, there were four only, in xix to xxii, though the oesophagus was still rather 
firm in xviii. 
