124 JESSE LE ROY CONEL 



smaller corpora lutea. The writer is unable to explain what is 

 the final fate of the corpora lutea, unless they form some of the 

 small brown oval bodies which will be described later. It seems 

 improbable that they are completely absorbed. The fact that, 

 as noted above, there are no intermediate stages between eggs 

 about 2 mm. long and the large ones, and that also in animals 

 which have corpora lutea, the eggs present do not exceed 2 mm., 

 is interpreted to mean that as soon as some eggs exceed 2 mm. 

 in length all the other eggs are arrested in development until 

 the larger ones have matured and have been passed from the 

 body, and their corpora lutea are well along in the process of 

 degeneration. 



Distributed comparatively uniformly along the entire mes- 

 ovarium, wherever eggs occur, are numerous brown oval bodies 

 which measure approximately 0.5 by 1 mm. They are some- 

 what flattened laterally, and are located proximally to the 

 smallest eggs. None of these brown bodies are present in the 

 youngest specimens, but they occur in all adult females, being 

 most numerous in the older ones. In the mesovaria of some 

 of the latter, for example specimen no. 9, there are no eggs, but 

 many of these brown bodies. Since only comparatively a few 

 eggs become larger than 2 mm., many eggs do not attain com- 

 plete development, but degenerate. The brown bodies are the 

 degenerated eggs and their envelopes. Intermediate stages of 

 degeneration between the brown bodies and the normal eggs occur 

 occasionally. It is possible that some of the brown bodies repre- 

 sent degenerated corpora lutea, though none were found whose 

 structure would indicate this. As shown in figures 71, 72 and 

 73, representing sections of three stages of these, the mesovarium 

 envelopes the brown bodies in the same manner as it does the 

 small eggs (fig. 74), but the walls of the envelope around the 

 former are much thicker. Also, numerous blood capillaries occur 

 between the envelope and the former membranes of the egg, 

 which have been converted into convoluted strands of connec- 

 tive tissue. The center of the brown bodies is filled with round 

 nuclei and dark-yellowish granules which may be the remains 

 of the yolk and which cause the brown color. 



