106 
FRANK E. BEDDARD. 
External Characters. 
The length of the largest specimen is about five inches. 
The arrangement of the seta is shown in fig. 9 of PI. XIII. 
A prostomium is present (PI. XIII, fig. 4), but does not 
completely divide the circumoral segment. The clitellum 
is well developed in one of the two specimens which I examined ; 
it occupies segments 14, 15, and 16, having therefore precisely 
the range which characterises so many species of Perichajta; 
as in that genus the glandular modification of the epidermis of 
the clitellar segments is continuous right round the body, 
being equally well developed upon the ventral and upon the 
dorsal surface (PI. XIII, fig. 3, cl.). 
The only apertures visible upon the outside of the body (see 
PI. XIII, fig. 3) are the dorsal pores, the apertures of the 
male and female reproductive ducts, and of the spermathecse. 
No nephridiopores could be made out. The dorsal pores com- 
mence between the 11th and 12th segments. The oviducal pores 
are upon the fourteenth segment ; they are paired and situated 
a little in front and to the inside of the ventralmost seta. 
The apertures of the atria are, as in Acanthodrilus, two 
pairs : one pair are upon the seventeenth, the other upon the 
nineteenth segment ; they correspond in position to the outer 
seta of the ventral pair. The spermathecal pores are close to 
the anterior border of segments 8 and 9 ; they correspond in 
their relation to the setse with the male pores. 
Internal Anatomy. 
Integument. — PI. XIII, fig. 10, illustrates a section 
through the body wall, in the hinder region of the worm. 
The section has been drawn with the aid of a camera lucida, 
and therefore indicates correctly the relative thickness of the 
different layers, which together constitute the body wall. As 
appears to be almost always the case, the longitudinal muscles 
are much thicker than the circular ; in this worm they are 
about six times as thick. 
