218 MR. F. E. BEDDARD ON | Mar. 3, 
therefore to be possible that, after all, in spite of undoubted 
resemblances, Michaelsen and I have examined different species 
and indeed different genera. 
The female organs of the species which I have examined show 
a number of not uninteresting features. The two most salient 
parts of that system, which are visible on a dissection, are the two 
spermathece and the egg-sacs. The spermathece are sausage- 
shaped, and distinctly divisible into two regions. The proximal 
part, ¢. e. that nearest to the external orifice, is strongly muscular, 
and indeed is enveloped with stronger muscular bands than is the 
bursa propulsoria of the spermiducal gland. Its epithelium is 
perfectly continuous with the general epidermis of the body-wall, 
and it has every appearance of being formed as an ingrowth from 
the exterior. The distal region of the spermatheca has very thin 
muscular walls, much thinner than the walls of the glandular part 
of the spermiducal gland. 
The interior has an epithelium which is raised into folds. I 
cannot speak of the histological characters of the cells, as the 
material was not sufficiently good. There is a very close resem- 
blance, on a superficial view, between this spermatheca and the 
spermiducal glands. Indeed, on a cursory inspection, they 
might be taken for consecutive pairs of either spermathece or 
spermiducal glands. The next most obvious part of the female 
reproductive system is a very large mushroom-shaped body closely 
adherent to the septum dividing segments xiii./xiv. This body is 
stalked, and appeared, on dissection, too large to be identified 
with a receptaculum ovorum (or egg-sac). Nevertheless it is the 
egg-sac, and by virtue of its large size it appears to be precisely 
like the egg-sac of P. papillata described by Michaelsen. On a 
closer inspection, a fine tube, apparently leading from the stalk 
of the egg-sac to the muscular part of the spermatheca, was 
apparent; this seems to correspond to the narrow tube (sq.) figured 
by Michaelsen. 
A series of longitudinal sections through the body showed more 
accurately the relations of these diverse organs to each other. I 
find that the spermatheca is entirely independent of the rest of 
the female apparatus, and that its cavity does not communicate 
with the narrow tube arising from the ege-sac. That narrow tube 
exists, as I have already mentioned; but on reaching the base of 
the spermatheca, 2. e. the muscular end portion, it dilates into a sac 
which entirely surrounds the muscular part of the spermatheca, 
but does not, so far as I could ascertain, open into it anywhere. 
The conditions, therefore, are those of such a genus as Hyperio- 
drilus or Helhiodrilus, where a true spermatheca is invested by a 
ceelomic sac. Now, though the difference may appear to be slight, 
I am disposed to think that it is important, and that a sperma- 
theca which has no communication with the egg-conducting 
apparatus is essentially different from a spermatheca which has 
such acommunication. It seems to me, for example, to be wrong to 
compare the spermathecal sac of Lybiodrilus or Stuhlmannia with 
