222 FRANK E. BEDDARD. 
only known in the genus Eudrilus, and in the not very nearly 
allied Nemertodrilus. Nevertheless, a more detailed study 
of the worm has convinced me that it is an entirely distinct 
genus, showing, except for the paired apertures of the genera- 
tive ducts, no particular likeness to any Eudrilus with which 
I am acquainted. It is probably true that the genus Eudri- 
lus requires revision. It is possible that the individuals from 
Africa, America, New Zealand, &c., differ specifically among 
themselves. I confess that I have not been able to detect any 
such differences, and I am at a loss to understand by what 
characters Dr. Horst distinguishes his Eudrilus jullieni, 
though I admit that he only creates the new species in a very 
diffident manner. On the other hand, Michaelsen’s Eudrilus 
pallidus is, in my opinion, unquestionably a distinct form. 
These two species of Eudrilus and Nemertodrilus griseus 
are at present the only Eudrilids with paired genital pores. 
These Michaelsen places in a distinct sub-family from the 
members of the family, the great majority of which have 
median unpaired pores. I shall attempt to show in the sequel 
that this character is not alone sufficient to distinguish two 
such groups; that the resemblances between the genus Par- 
eudrilus and certain genera of the sub-family Teleudrilini is 
closer than that which obtains between Pareudrilus and 
Eudrilus. 
The colour of this worm is a dark purplish brown upon the 
dorsal surface, becoming light below. The colour was not well 
preserved in specimens that had been treated with Perenyi’s 
solution. In a single individual, which was brought home 
alive and preserved by myself in gradually increasing strengths 
of alcohol, the colour was very dark, as dark as during life ; it 
was much bluer than the rest. All the specimens were found 
either in the mud at the edge of a pond on Mombasa Island or 
from a bog up country about four miles from the coast line 
opposite to Mombasa. The length of a worm selected for 
measurement was 63 mm., the breadth 4 mm.; this represents 
about the average size. The prostomium is continued for a short 
distance on to the peristomial segment by two grooves enclos- 
