MINOT. 453 
EXPLANATION OF PLATES. 
Nearly all the figures were drawn by Mr. E. Stanley Abbot under my supervision. 
The outlines were drawn with the camera lucida, and the details added free-hand. 
The drawings are all accurate representations of the preparations, and though of 
course not photographically exact, are not diagrammatic, except in the case of a few 
figures expressly specified below. I owe much to Mr. Abbot’s patient skill. 
Reference Letters. 
all, allantois. 
cm, circular muscles. 
conn, connective tissue. 
ecto, foetal ectoderm. 
emé, embryo. 
en, entoderm. 
endo, endothelium. 
ep, epithelium. 
J; placental fissure. 
Sv, foetal blood-vessel. 
gt, gland; glandular layer. 
h.ep, hyaline epithelium. 
Z, leucocytes. 
/m, longitudinal muscles. 
mes, mesoderm. 
mo.cl, monster cells. 
misth, mesothelium. 
miuc, mucosa. 
musc, muscularis. 
ob.pl, ob-placenta. 
0.2, outer zone of placenta. 
P, periplacenta. 
perv, perivascular cells. 
sp.pl, sub-placenta. 
Sel.z, subglandular zone. 
V, blood-vessel. 
vac, vacuole. 
