32 PROCEEDINGS OF THE ACADEMY OF [Jan., 



favors the view that such a movement is the result of an actual 

 motility, of the microgametes themselves. It may also be that in 

 life the macrogametes are amoeboid and gain their subepithelial 

 situation through their own motility, but here the probabilities are 

 the other way. Analogy is not in favor of a belief that the macro- 

 gamete is motile, nor do the macrogametes ever show amoeboid 

 outlines in the fixed material. 



As to the actual situation of the parasites which occur beneath 

 the epithelium, the fixed material does not give wholly conclusive 

 evidence. They appear, however, to occur rather between the row 

 of cells and the stroma than in the stroma itself. 



We thus have obvious male elements and obvious female elements 

 occurring beneath the row of epithelium cells. The production of 

 male and female cells necessarily involves their union, and the 

 environment in which they both occur offers no obstacle to such a 

 procedure. It is evident that the proper demonstration of such a 

 process should be made upon living material, since, in a situation 

 such as has been indicated, the identification of a minute fragment 

 of highly basophil matter as a microgamete is largely a matter of 

 guess-work. It is easy enough to identify the thread-like bodies 

 of figs. 75 or 76 as microgametes, since here their relationships with 

 their surroundings can be established. But it is clear that an isolated 

 microgamete cannot be identified when it occurs in a region pre- 

 senting such a confused picture as does the subepithelial tissue of 

 the mammalian intestine. 



Nevertheless, when the macrogametes as they occurred in the 

 subepithelial tissues of mouse 152 were studied, it was possible to 

 separate them into two categories. A certain number were as 

 figs. 88 to 91. Others were as fig. 93. These differ only that in the 

 latter there was present in the cytoplasm a sharply basophil body. 

 Also, conditions such as are illustrated in fig. 92 were found, where 

 two elongated sharply basophil bodies are seen either lying upon or 

 partly within the cytoplasm of a macrogamete. In consideration 

 of the fact that it is axiomatic that the development of males and 

 females involves fertilization, the indirect evidence here offered as 

 1o the actuality of the process seems satisfactory. Fig. 92 shows 

 two supposed microgametes associated with the macrogamete, but 

 it is safe to conclude that only one would have been successful in 

 effecting union. 



The three cells shown in fig. 93 have somewhat irregular outlines, 

 this being the condition as found. Assuming that this is not an 



