ON THE FATE OF THE HUMAN EMBRYO IN TUBAL PREGNANCY. 49 



probability this was a case of interstitial implantation with the crescent-shaped 

 lumen of the tube on one side. In many respects the attachment to the tube wall 

 and active trophoblast is much like that seen in No. 808, which contained an almost 

 normal embryo. The villi are partly normal in appearance and partly edematous. 

 The trophoblast over the villi is very active, especially where these come in contact 

 with the tube wall. At these points they might pass for normal villi and trophoblast. 



About 6 specimens remain, which show the fate of an attached ovum extending 

 into the organized clot within the tube lumen. In all of these specimens the lumen 

 encircles more than one-half of the clot, so that it is impossible to determine, with 

 any degree of certainty, whether we are here dealing with a true interstitial implan- 

 tation or whether the ovum was attached only to a fold in the tube wall, as is well 

 illustrated in specimens Nos. 415, 473, and 418. The first specimen of this group 

 (No. 659) contains a well-formed clot, having in the center a few small fibrous villi. 

 Some of these, in turn, are encircled with a narrow zone of fresh blood. Another 

 specimen belonging to this group (No. 575) contains a coelom 5 mm. in diameter; 

 that is, the ovum did not collapse. Between the coelom and the tube wall is a mass 

 of radiating fibrinoid tissue with scattered villi covered with necrotic trophoblast, 

 containing much nuclear dust. Some of the villi are also necrotic, some are under- 

 going mucoid degeneration, and others are fibrous. A few of them are encircled 

 with a zone of fresh blood. Curiously enough, these are undergoing mucoid 

 degeneration. No. 726 gives an appearance similar to that in No. 659, excepting 

 that the distention of the tube is greater. Here the description of No. 575 could 

 also be applied to this specimen. There are a few fibrous villi and a few which have 

 undergone mucoid degeneration. These latter are also encircled by a zone of 

 fresh blood. 



Nos. 762 and 809 can be taken up together, as in many respects they are alike. 

 In both the tube wall contains an extensive hemorrhage, which has not become 

 organized to any great degree. Both contain scattered fibrous villi, a ramified 

 system of fibrinoid substance, and a great marked invasion of leucocytes. These 

 pass along the line of the fibrinoid substance. At some points the villi are being 

 destroyed by the leucocytes. 



The group of specimens in which the ovum has become fairly well implanted 

 in a fold of tube wall differs in several respects from a group in which the ovum 

 lies free within the tube lumen. In the former the ovum grows to a larger size 

 before it begins to degenerate, there is a more marked hemorrhage, and the degenera- 

 tion of the ovum is delayed; in other words, there is a greater mass of necrotic 

 tissue to undergo destruction. 



The remaining group to be considered consists of ova which have become well 

 implanted in the tube wall and contain practically no remnants of the embryo. 

 Such a specimen usually contains a well-defined ccelom, and occasionally a very 

 small remnant of an embryo may be detected. It is probable that the embryo was 

 present in more of the cases, but was overlooked. This group is to be viewed as a 

 continuation of the one containing pathological embryos. In the further course 

 of destruction the embryos gradually disintegrate and finally the chorion is left 



