HYDATIFORM DEGENERATION IN TUBAL PREGNANCY. 239 



ceived from Dr. Vest. In this specimen the two chorionic vesicles, the intervillous 

 spaces of which were devoid of blood, lay in almost the same transverse diameter of 

 the tube, and hence had distended the latter considerably. Both were implanted 

 quite well over the entire area of contact, which included the whole perimeter of the 

 tube. The chorionic vesicles were flattened at the region of mutual contact, which 

 divided the tube somewhat unequally (fig. 13, plate 2, Chap. IV). Although the 

 embryo and the amnion long had disintegrated completely, and although the 

 chorionic membrane itself is thin, covered by degenerate epithelium and also dis- 

 integrating, the epithelium of the villi not only is well preserved, but is accompanied 

 by large masses of trophoblast and considerable syncytium. Syncytial buds are 

 found on the chorionic membrane also. The tubal mucosa is largely and the 

 tubal wall partly destroyed by the invading trophoblast. Only a few small vestiges 

 of the walls of the villous vessels remain, and the stroma of all the villi has under- 

 gone changes characteristic of hydatiform degeneration, as represented in figure 

 136. One villus also contains an epithelial cyst resulting from epithelial invagi- 

 to nation with subsequent isolation of the distal extremity, a process to be referred 

 later in connection with uterine specimens. Since most of the villi of this and 

 similar specimens still are implanted in the tube, there can no longer be any ques- 

 tion as to the time in which hydatiform changes in the stroma of the villi may 

 be inaugurated. As illustrated in other instances in which isolated and small 

 groups of villi were still implanted, the advent of degeneration of the stroma occurs, 

 in part at least, before the villus is detached. Hence it is not merely a post-mortem 

 or maceration change. 



Another very interesting specimen of tubal implantation is No. 1771, received 

 from Dr. H. M. N. Wynne, of the Johns Hopkins Hospital. The menstrual age of 

 this specimen is 49 days, but its anatomic age, as based upon length according 

 to Streeter's (1921) curve, is 37 days, thus showing a discrepancy of 12 days 

 between the menstrual and anatomic ages. The embryonic length is only 12.5 

 mm., although with a menstrual age of 49 days it should be at least 18 mm. 

 Upon examination, Streeter found the chorionic vesicle to contain a good deal of 

 magma, some of which was still adherent to the embryo, as figure 148 (plate 14, 

 Chap. X) shows. As has been repeatedly emphasized in the literature, the presence 

 of this coagulum in itself probably indicates that the embryo died some time 

 previously. 



The wall of the tube is quite thin, as figure 138 shows, but the implantation is 

 fairly well preserved around the whole perimeter of the specimen. The mucosa is 

 destroyed throughout the greater extent of the section and the trophoblast is 

 abundant, except in one rather degenerate and hemorrhagic area. The chorionic 

 membrane is thin, but contains some vessels distended with blood. The stroma of 

 many of the villi also contains vessels filled with blood, but the vessels in many 

 others are very evidently in degeneration. The syncytium is scanty, and many 

 of the villi are very plainly hydatiform, as seen in figures 137 and 139. 



A third exceptionally fine specimen of tubal hydatiform mole is No. 2052, 

 donated by Dr. C. L. Davis, of Washington, District of Columbia. Figure 140 

 shows a portion of the tube containing a hydatiform mole, some hydatiform villi 



