484 PROFESSOR TURNER ON THE GRAVID UTERUS AND 



amnion the chorion formed the sole constituent of the foetal membranes. 

 Not only was the amnion surrounding the cord abundantly studded with 

 yellowish brown or olive-tinted bodies, smaller even than mustard seeds, but 

 they were also thickly congregated on the amnion where it covered the 

 funnel-shaped sac and horns of the allantois, though they were much more 

 sparingly distributed on that part of the amnion which was in contact with the 

 chorion (fig. 7, d). In the right cornu they were absent on that portion of the 

 amnion which extended beyond the horn of the allantois, but on the left side 

 they extended further, and one was seen almost at the closed end of the 

 amnion (fig. 7, d'). By the presence of these corpuscles in connection with 

 the amnion, and their absence on the free surface of the allantois, these two 

 membranes were at once readily distinguished from each other. Some of these 

 corpuscles were pedunculated, others sessile, and they had obviously been 

 developed in relation to the attached, and not to the free surface of the amnion, 

 for each was invested by a prolongation of that membrane (as the spleen is 

 invested by the peritoneum), and, where the corpuscles were pedunculated, the 

 pedicle of attachment, which sometimes was ^th of an inch long, was formed 

 by a slender filamentous process of the amnion. Thin sections of the corpuscles, 

 examined with a magnifying power of 480 diameters, were found to be composed 

 of cells, closely packed together, some of which were oval, others somewhat 

 elongated, others somewhat polygonal in shape. In many of the cells clusters 

 of brown pigment granules were contained (fig. 8). 



The amnion and allantois were connected together by a very delicate fila- 

 mentous tissue, in which a few tortuous slender branches of the umbilical 

 arteries and veins were distributed, and frequently formed well-marked anasto- 

 mosing loops. When the amnion and allantois were separated from each other, 

 these vessels remained in contact with the deep surface of the former membrane. 

 By dissecting off the amnion from the cord, numerous vasa vasorum could be 

 seen distributed to the coats of the umbilical vessels and the urachus. 



I also found between the amnion and allantois, close to the trunks of the 

 umbilical vessels which passed to the left horn, three peculiar-looking bodies, 

 the blood-vessels of which were injected from the above-mentioned amniotic 

 arteries. The largest, tri-radiate in form, was § inch long by \ inch in greatest 

 breadth, the others were much smaller, and of an ovoid form. They lay in 

 linear series, the highest and largest was 1^ from the second, and that again \ 

 an inch from the third. They were connected together by intermediate vessels, 

 and resembled in appearance a chain of small lymphatic glands. When the 

 allantois and amnion were separated from each other, these bodies remained 

 attached to the amnion. When a section was made into one of these bodies, a 

 brown pultaceous mass, contained within a cavity, the wall of which was formed 

 of a fibrous capsule, was exposed. The brown mass, examined microscopically, 



