NEW TAPEWORMS FROM THE HYRAX. 589 



examination of the cavities seems to show that they are lined by 

 a flattened epithelium, of which the nuclei are apparent and are 

 represented in the figure, and there is a slight accentuation of 

 the wall of the cavity, which is merely, as I think, the portion 

 of the parenchymatous network which abuts upon the cavity and 

 is not a special layer distinct from that ; in this case the ap- 

 parent lining epithelium should be regarded merely as the nuclei 

 belonging to this part of the parenchymatous network. I believe 

 this to be the leal explanation ; for when we look carefully into 

 the cavity itself, in which eggs lie in vai'ious numbers, there is 

 nearly always, if not quite always, some granular detritus to be 

 seen and which is shown in the figures referred to. This formless 

 detritus (as it often, but not always, is) might, of course, be inter- 

 preted as simply coagulated fluid which it would not be surprising 

 to meet with in the interior ^of a uterus were this system of 

 cavities the remains of a uterus. But, as will be seen, this 

 detritus is susceptible of another explanation ; it is, as I think, 

 the remains of the delicate parenchymal network originally 

 present, as is shown in text-fig. 77 A, in these regions of the 

 parenchyma set apart for the development of the eggs. The 

 figure referred to shows plainly an area oval in section and with 

 a slightly accentuated wall, marking it off from the surrounding 

 tissue, which is filled with parenchyma network, but does not as 

 yet contain any eggs. If my contention is right, then it must 

 follow that the space containing developing eggs is at least not 

 always to be referred to a uterus. Nor is it in the least against 

 this view that it is possible to meet with these circular spaces in 

 which nothing is apparent but eggs — that is to say, no remains 

 of the originally present parenchymal network, for this may have 

 completely disappeared. I would furthermore point out that 

 the position of the eggs in the nearly empty cavity shown in 

 text-fig. 77 B suggests that they have only just forced themselves 

 into the cavity. 



I have yet another argument to show reason against regarding 

 the cavities of the paruterine organs in which the embryos are 

 finally lodged as detached fragments of the pre-existing uterus ; 

 or, at any rate, to show that they cannot always be so regarded. 

 In text-fig. 77 b and text-fig. 76 is represented an ovum lodged 

 in one of the meshes of the parenchymatous network of the 

 medullary region without any special relation to the larger egg- 

 containing cavities which have been looked upon as detached 

 fragments of a uterus. There are plenty of such examples to 

 be seen in sections of this age, and it is plain to me that eggs are 

 constantly lodged singly in the parenchymal network. I argue 

 this from the fact that in these cases the cavities lodging the ' 

 eggs are in every way indistinguishable in size and appear- 

 ance from the cavities of the parenchyma in which an egg is 

 not lodged. It may be, of course, that these are eggs which 

 got extruded from a uterine cavity and forced into the sur- 

 rounding parenchymatous network. But it is equally reasonable 



