ON THE FATE OF THE HUMAN EMBRYO IN TUBAL PREGNANCY. 29 



the embryo, which is 6.5 mm. long. The villi of the chorion show marked degen- 

 erative changes, but at some points the trophoblast is active. The chorionic wall 

 appears to be somewhat fibrous, but is rich in blood-vessels. In the sections the 

 exocoelom contains a dense reticular magma through which both embryonal and 

 maternal blood cells are scattered. Upon the wall of the chorion are several dense 

 plaques of trophoblast, more especially evident at places where the chorion comes in 

 contact with fresh blood. We have here a specimen which to all appearances is 

 pathological. The hemorrhage is so extensive, the blood clot is so thoroughly 

 organized, and the amniotic cavity is so very small, that it is surprising that an 

 embryo, normal in appearance, should be found within it. Most of the tissues are 

 quite active and certain groups of trophoblast cells appear to be normal; otherwise, 

 the villi are degenerating. It appears, then, that only a few villi are necessary to 

 nourish the ovum properly. 



In the next specimen (No. 612), the changes of the chorion are not so pro- 

 nounced. The chorionic wall is very vascular and unusually fibrous for one con- 

 taining an embryo so small. The amnion is also well formed and in apposition with 

 the chorion. The villi are well developed and upon their tips is a very extensive 

 trophoblast. At some points are large areas of vacuolated syncytium. The tro- 

 phoblast comes in close contact with the tube wall and is partly separated from it 

 by remnants of its epithelial lining. To all appearances the implantation is normal 

 with an exceptionally large amount of organized blood clot between the chorion 

 and the tube. We have here an excellent example of an ovum, well nourished 

 despite the fact that the intervillous spaces are entirely plugged with blood clot. 

 The villi have perforated this clot and are well attached to the tube wall. The clot 

 is stratified, that is, it is composed of alternating layers of fibrinoid tissue and blood, 

 and it is also well infiltrated with leucocytes. At points where the villi are dying 

 the leucocytes form large colonies. The trophoblast within the clot has also a 

 peculiar appearance, the great amount of hyaline matter between the individual 

 nuclei making it look like cartilage. At any rate, the changes are so pronounced 

 that we can not possibly look upon the clot between the villi as forming a normal 

 circulation. We have really a red infarction through which the villi extend to get 

 their nourishment from the tube wall. 



Specimen No. 597 contains an embryo 9 mm. long, which appears to be nor- 

 mal. It is encircled by a narrow zone of blood which is not organized, but within 

 which there are many necrotic villi. There are also marked signs of inflammation 

 and a little active trophoblast. There is some vacuolated syncytium, undergoing 

 necrosis. It is quite difficult to understand why a specimen like this should contain 

 a normal embryo. Possibly the embryo had been dead for some time, as its tissues 

 are soft and there were extensive necrotic changes in the chorion. We appear to 

 have here, in the specimens just described, stages of degeneration of the ovum with 

 embryos up to 10 mm., showing partial or complete destruction of the chorion and 

 the ultimate death of the embryo. The embryo 4 mm. long was undoubtedly alive 

 at the time of the operation, and the embryo 9 mm. long was undoubtedly dead. 

 Between these two extremes we have a gradual increase of the amount of blood 



