386 MINOT. [Vot. II. 
from other embryonic connective tissue cells. Their bodies 
have little affinity for coloring-matters, hence it is difficult to 
follow the processes by which the cells are united. Their 
nuclei are at first round or oval. After the third month they 
often show a great variety of alterations in shape and size, Cuts 
g, 10; some of the nuclei are then very large, with a distinct 
net-work, d; others are smaller and differ but slightly from the 
normal; some are very irregular, 6, and others again strangely 
elongated, @; many other forms beside those represented in 
Cut g are to be found. The changes indicated I consider of 
a degenerative character, and in fact many of the nuclei are 
Cut 9. — A natural group of nuclei from the mesoderm of the amnion of a foetus 
of the fifth month. XX 1225 diams. 
breaking down, for one finds in some specimens every stage be- 
tween a nucleus and scattered granules, — nuclei, nuclei with in- 
distinct membranes, nuclei without membranes, masses of gran- 
ular matter, clusters of granules crowded together, and finally 
other clusters more or less scattered. This degenerative pro- 
cess may be compared with that described by Phisalix (Arch. 
Zool. Expt., Sér. Il., T. III., 382) as occurring in the blood cells 
of the spleen of teleosts. Compare also the chromatine degen- 
eration observed by Flemming to occur in ova of the vertebrate 
ovary (Hzs and Braune’s Archiv. 1885, 221-244). In the human 
amnion the nuclear degeneration described is not always to be 
recognized so clearly, although the nuclei in all amnia older 
than three months, which I have observed, are more or less 
