148 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



other animal, for the simple reason that they are also in- 

 ternal, yet it was conceivable that they represented 

 enormously modified and hypertrophied ova, which had 

 become detached from the genital stroma (germinal epi- 

 thelium) when very young, had been carried about — 

 absorbing a great quantity of nutriment which had formed 

 the remarkable chromatic development — and thus finally 

 grown into these huge cysts.* Unlikely as this hypothesis 

 might at first sight appear there were two or three points 

 in favour of it, and I have, therefore, carefully considered 

 it. For one thing, the resemblance between the nucleus 

 of one of these bodies and that of a flounders egg is quite 

 striking. Though differing greatly in size (and I may 

 here say that the diameter of a cyst averages about four 

 times that of a normal egg, and the nucleus is relatively 

 larger), their structure is practically identical. Indeed, 

 the nucleus reminds me more of a germinal vesicle than 

 anything else. It is not like a Protozoan nucleus, that of 

 a Gregarine being the only one which can be compared 

 with it, from which this differs chiefly in relative (to say 

 nothing of absolute) size, and in the ill-defined mem- 

 brane, lacking any marked affinity for the chromatin 

 stain. The outermost layer (ect.) would also serve for a 

 thick egg-membrane, but in none of my sections is any 

 radial striation visible, corresponding to the " zona 

 radiata " of the eggs, although I should add that 

 Sandeman mentions and figures something of the kind 

 in his description. The chief difference is in the cortical 

 zone. Whereas, in an egg, the cytoplasm is filled with 

 large, spherical, refringent, oil or fat globules, there is not 

 the least sign of such in the cortex of these bodies 



*I should prefer to think of their origin thus (i.e. , from differentiated 

 ova, however small), than to suppose they had originated from wander- 

 ing ("vagrant ") indifferent germ cells, — because of their single and 

 markedly ovarian nature. In the latter case, there would more 

 probably have resulted (by proliferation) "cell-nests" of ordinary 

 indifferent cells. 



