PHYSIOLOGICAL PROPERTIES OF GONADS 159 



cernible; these latter masses are the characteristic groups of 

 interstitial cells. A considerable amount of the fimbria of the 

 oviduct accompanies the section of the ovarian tissue. 



Graft 2. This section, somewhat larger than the previous 

 one, consists of about 300 sections of ovarian tissue. Here also 

 the medulla and cortex are characteristic, and some twelve to 

 fifteen normal follicles are present as well as scores of all sizes 

 of atretic follicles. Figure 6 shows one follicle whose ovum 

 has just completed the formation of a polar body; the ovum is 

 yet surrounded by the discus proligerus though this is apparently 

 undergoing dissolution. Sections of the oviduct accompany 

 this graft. 



There is no indication either of corpora lutea or of ovulation 

 in these two grafts. 



Animal 51 D. Male, born Feb. 27, '18. Operation Apr. 13, one 

 testis removed (one undisturbed) ; two small pieces of ovary from sister 

 placed subcutaneously and intraperitoneally. Aug. 22, '18, killed; the 

 remaining testicle was normal as well as sperm sacs; both ovarian grafts 

 had persisted for 130 days; both grafts sectioned. 



Microscopic examination. Each of the grafts has suffered a 

 considerable amount of resorption and around the edges of the 

 ovarian tissue there is distinct evidence of degeneration and con- 

 nective-tissue proliferation. 



Graft no. 1 consists of but sixty or sixty-five sections of ovarian 

 tissue, but within this small amount there are several distinct 

 follicles, a few of the smaller ones apparently normal, but the 

 larger ones atretic. 



The especial interest attached to this graft is the presence of 

 two distinct and separate bodies of cells; these cells are larger 

 than the cells found in any other part of any of the graft material, 

 and they appear to represent unmistakable, though small, 

 corpora lutea. They are somewhat removed from the surface 

 of the graft and are surrounded by stroma cells. 



If these are small corpora lutea (and there seems nothing to 

 indicate the contrary) the question of their origin presents itself. 

 As has been repeatedly mentioned, no structure or condition in 

 any of the grafts has given the least evidence that ovulation has 



