220 MALL. [Vot. XIX. 
where. There are no cranial nerves. The heart is a vesicle 
filled with blood, hanging into the ccelom and slightly at- 
tached to the body wall. Its vascular connection with the 
body is cut off entirely. The blood-vessels of the body are 
irregular in shape and entirely changed from the normal 
Fic. 189a.—Photograph of the embryo. Enlarged 2 times. 
Fic. 189b.—Section through the head of the embryo. 30 times. The 
medullary plate, m, is open throughout its whole extent. 
type. They are filled with blood which extends through their 
walls into the surrounding tissues. The branchial arches cor- 
respond to an embryo of this size. There are still traces of 
optic vesicles, chorda and possibly allantois present, the liver 
and stomach and intestine having degenerated. 
No. 190. 
Ovum, 25°x 22 x 12 7m. 
Dr. C. M. Ellis, Elkton, Md. 
The ovum is filled with reticular magma within which no 
trace of an embryo can be found, although the entire specimen 
was stained and cut into serial sections. The chorion and 
villi are apparently normal, containing blood-vessels from the 
embryo. 
