ON THE FATE OF THE HUMAN EMBKYO IN TUBAL PREGNANCY. 35 



wall is well formed and contains a few long, slender villi ramifying in the blood clot. 

 The trophoblast is scanty, but there are a few small knobs of syncytium upon the 

 main wall of the chorion. It appears as though the ovum had become gradually 

 detached and that its nourishment was gradually cut off, so that it ultimately 

 resulted in a stunted embryo. We have here a repetition of what is often seen in 

 ova expelled from the uterus. A stage less advanced than this, in fact intermediate 

 between that in No. 808 and that in No. 324, is found in specimen No. 396. The 

 tissue is unusually well preserved and the chorionic mass was cut into serial sec- 

 tions. According to the clinical history, the duration of pregnancy was 31 days. 

 The relation of the chorion to the tube wall is practically identical with that in 

 No. 808. The ovum is small, the villi are reaching out in tufts and radiating 

 through an extensive freshly formed blood clot to implant themselves well in the 

 tube wall. However, in one respect the two specimens are markedly different. In 

 No. 396 the chorionic vesicle contains the remnant of a deformed umbilical vesicle 

 and a small remnant of an embryo, as shown in plate 5, figure 1. Between the 

 umbilical vesicle and the chorionic wall is a considerable amount of reticular magma 

 with patches of maternal blood. The chorionic wall itself is fibrous, thickened, and 

 contains numerous irregular blood vessels filled with blood. Some of the villi reach- 

 ing out toward the chorion have likewise undergone fibrous degeneration. Although 

 the trophoblast is very active, numerous long strands of cells radiate from it through 

 the blood clot. In many instances these cells are undergoing degenerative changes. 

 There also seems to be fresh hemorrhage encircling the trophoblast. It may be 

 that the implantation was disturbed and the nourishment of the embryo was 

 effected thereby. We have repeatedly observed that the most susceptible parts in 

 young ova are the embryo and amnion, the umbilical vesicle being more resistant. 

 This is emphasized again in this specimen, in which the embryo is more markedly 

 affected than the umbilical vesicle. No doubt if this specimen had continued for 

 some time, it would have become like the one containing the remnant of an ovum 

 embedded in a large mass of organized blood; that is, if the tube had been removed 

 at a later date the specimen would have fallen into group No. 3, which is to be 

 discussed presently. 



The two remaining specimens of this group, No. 554 and No. 697, may be con- 

 sidered together, as they exhibit practically the same changes. In the first the 

 chorionic wall and its villi are very fibrous and completely separated from the 

 uterine wall. Many of the villi are necrotic. The coelom contains granular magma 

 and a remnant of an embryo measuring about 1 mm. in length. It is composed of 

 round cells, but it is impossible to determine the outline of any of the organs. 



In the second specimen (plate 7, fig. 5) the ovum is more fibrous, that is, the 

 chorion is more fibrous and its cavity contains a nodule of round cells looking much 

 like a section of lymph gland. Strands of trophoblast pass through a very large 

 blood clot and some of it is still connected with the tube wall. At one point the 

 syncytium is vacuolated and enters some of the venous sinuses. 



This group taken together gives about the following story: If the ovum is 

 detached early, the embryo first disintegrates and ultimately the umbilical vesicle 



