216 FRANK E. BEDDARD. 
esting discovery of the course of the nephridial tube in certain 
species of Lumbricus (or Allolobophora) will occur to the 
reader. The facts discovered by Hubrecht, which I can 
confirm by my own experience, seem to be analogous to those 
described here. In those worms Hubrecht found that the 
nephridial duct, after entering the body-wall, passed along it 
between the two muscular layers to the opening, which is 
situated in some cases beyond the outer pair of set; there is, 
however, no question, in Lumbricus, of an integumental 
plexus. Still it is possible that there may be in this peculiar 
disposition of the nephridial duct in some Lumbricide a re- 
semblance to the Eudrilide. We may have here a clue to the 
affinities of the Lumbricide, which has been hitherto wanting ; 
but I do not propose to follow up this matter at present. 
Reproductive Organs.—The sperm mass of the 11th 
segment is, like that of the next segment, apparently not 
enclosed in a sac. When the worm was dissected the mass 
of sperm could be easily disturbed by the dissecting needle. 
There was nothing to offer any resistance to the needle. 
There is, however, seemingly a functional equivalent of the 
missing sac. The septum which bound this segment pos- 
teriorly is comparatively thin, though thicker than the septa 
in the posterior region of the body. It is inserted on to 
the body-wall in the usual way. Just before its insertion a 
sheet of muscular tissue, of precisely the same thickness and 
general appearance as the septum, arises from the said sep- 
tum and passes obliquely forwards, ultimately joining the 
anterior septum of the segment which encloses the mass of 
sperm. There is thus formed a chamber which encloses 
the mass of sperm, but which does not seem to be the exact 
equivalent. of the sperm-sacs of other earthworms. It is 
well known that in many earthworms the successive septa are 
bound together by muscular bands running in various direc- 
tions. This state of affairs is more especially characteristic of 
the anterior and often thickened septa. It is probable, there- 
fore, that the materials for the formation of the septum above 
described already exist, and that the sheet of tissue which 
