OVARIAN PREGNANCY. 259 



Bryce, Teacher, and Kerr have given an excellent review of the literature on 

 ovarian pregnancy and Serebrenikowa has presented it from another standpoint. 

 Both of the papers demonstrate that in ovarian pregnancy no decidua is formed, 

 showing that a true decidua can not arise from the tissues of the ovary. 



Since the cavity containing the ovum in ovarian pregnancy does not always 

 seem to be encircled by a layer of lutein cells, it is concluded that the ovum either 

 invaded the ovary from its surface or that it burrowed from the Graafian vesicle 

 after fertilization. Undoubtedly the latter is the case in the specimen recorded 

 by Bryce, Teacher, and Kerr. In it the growing ovum broke through the layer 

 of lutein cells and made for itself a cavity in the vascular stroma of the ovary. 

 This conclusion could also have been drawn from our specimen had not a second 

 set of sections been made which shows that a beautiful and characteristic layer of 

 lutein cells is present. In the first set of sections the wall of the cavity was faulty, 

 while the second was perfect. We do not wish to question the accuracy of other 

 observers in this respect; we want only to record our own experience. At any 

 rate, the possibility of a secondary attachment of the ovum to the ovary through 

 its direct wandering from the Graafian vesicle into the adjacent tissue, or indirectly 

 through a reinvasion from the surface of the ovary, can not be denied until it 

 is shown that the ovum is invariably lodged in a Graafian vesicle and surrounded 

 by a layer of lutein cells of the same age as that of the ovum. Before this is pos- 

 sible it will be necessary to standardize the corpus luteum in relation to the ovum 

 and embryo, and also to present as evidence only well-preserved specimens of 

 ovarian pregnancy. 



Specimen No. 1522, which was donated to the Department by Dr. H. M. N. 

 Wynne, is a firm, nodular, dark-colored mass, 26 by 16 by 11 cm., shown in figures 

 163 and 164. In the gross, it especially recalls the specimens of Freund and Thome" 

 (1906), Giles (1914-1915), and Jaschke (1915), and Lockyer's (1917) second case. 

 The exterior is smooth though bosselated and formed by a rather injected layer which 

 is extremely thin, showing the blood-clot beneath, around the greater extent of 

 the specimen. The surface layer is eroded over several small elevated areas in 

 which the blood-clot underneath is exposed. Hence, the capsule may have been 

 ruptured in several or only in one of the areas as noted at the time of the operation. 

 Near the region of amputation through the mesovarium shown to the right in 

 the figure and marked by the corrugations of the hemostat, the tissue overlying 

 the clot becomes more opaque, thicker, and also more yellowish. Here it is studded 

 with small cysts, the character of which in itself suggests ovarian tissue. The 

 color of the area to the right is also suggestive, and the cysts later were found to 

 contain a clear, viscid fluid, so characteristic of cysts of the ovary. The location 

 of the main portion of the ovarian stroma shows that implantation occurred near 

 the mid-point of the free convex or posterior border of the ovary, and that the 

 stroma forming the sides gradually was forced apart, not by the growing con- 

 ceptus, except perhaps at the beginning, but mainly by the hemorrhage itself. 



The major portion of the surface of the divided specimen shown in figure 165 

 is composed of blood-clot, the presence of which confirms the "blood-clot crepitus" 



