164 Transactions of the Society. 
number of segments in relation to the length is very great, being 
about 190. 
The cliteUum being undeveloped and the male pores being invisible 
no clue to its affinity was afforded by its external character. 
The setae are eight in number in each segment, arranged in four 
couples. The outer couple, where the setae are close together, 
is lateral; the inner couple, i. e. that nearer the ventral mid-line, is 
ventro-lateral (figs. 3, 13) and the setae are further apart. 
If we take as our unit the distance separating the two setae of the 
outer or lateral couple, the inferior setal space is represented by 3, 
the lateral space, between the two couples, is 6 ; the ventral space 
between setae I and I is 6 ; the dorsal space between setae IV and IV 
is 18. 
Or written as a formula, i = 3 o and L = V = 6 o, where i = 
space between the two setae of inner couple, o = space between two 
setae of outer couple ; L means space between inner and outer couples 
of one side ; V = space between the inner couples. 
The setae themselves are small, measuring 0 • 135 mm., and are 
sharply hooked at their free extremity (tig. 4). 
The nephridiopores are visible under a lens, and are placed in a 
line with the outer couple, between the setae III and IV (figs. 3, 13). 
There are no dorsal pores. 
The prostomium is small and completely dovetailed into the 
peristomium or buccal somite (as in Lumbricus). In the specimen the 
prostomium was partly hidden, being bent into the mouth. 
The anterior 11 somites are much larger than the rest, they are 
more decidedly brown in colour, have thicker walls, and each is 
marked with a distinct ridge surrounding the body. 
The anus is terminal and circular; the circumanal somite is very 
small ; the penultimate and three or four previous preanal somites 
gradually widen out to attain the normal diameter of the worm 
(%, 2 ).‘ 
The Internal Anatomy. — Ihe arrangement of the internal organs 
was studied by means of longitudinal sections, but the general re- 
lations are shown in diagrammatic fashion by figs. 5 aud 16. 
The alimentary canal (fig. 5) consists of the usual thin-walled 
buccal region which lies in front of the cerebral ganglia in somite 
III. Immediately behind the latter lies the thick- walled pharynx, 
occupying somites III and part of IV, though appearing more 
extensive. The dorsal wall of the pharynx, as is always the case, is 
thicker than the ventral wall (see fig. 10), and this thickness is due 
in part to the groups of radiating and other muscle-fibres and in part 
to groups of gland cells which are arranged in strings between 
the radiating muscles (see fig. 12). 
These gland cells stain very deeply in borax-carmine, owing to the 
abundance of granules present in them, which almost conceal the 
round nucleus. 
