378 Labyrinthici and Holconoti 
“The female genital apparatus in the state of pregnancy 
consists of a large bag the appearance of which in the living 
animal has been described by Mr. Jackson. Upon the surface 
of it large vascular ramifications are seen, and it is subdivided 
internally into a number of distinct pouches, opening by wide 
slits into the lower part of the sac. This sac seems to be noth- 
ing but the widened lower end of the ovary, and the pouches 
within it to be formed by the folds of the ovary itself. In each 
of these pouches a young is wrapped up as in a sheet, and all 
are packed in the most economical manner as far as saving 
space is concerned, some having their head turned forwards 
and others backwards. This is, therefore, a normal ovartan 
gestation. The external genital opening is situated behind the 
anus, upon the summit and in the center of a conical protu- 
berance formed by a powerful sphincter, kept in its place by 
two strong transverse muscles attached to the abdominal walls. 
The number of young contained in this sac seems to vary. Mr. 
Jackson counted nineteen; I have seen only eight or nine in 
the specimens sent by Mr. Cary, but since these were open when 
received it is possible that some had been taken out. How- 
ever, their size is most remarkable in proportion to the mother. 
In a specimen of Emb. jacksont 10% inches long and 4% high 
the young were nearly 3 inches long and 1 inch high; and in 
an Emb. caryt 8 inches long and 3} high the young were 
22 inches long and } of an inch high. Judging from their size, I 
suspected for some time that the young could move in and 
out of this sac like young opossums, but on carefully examin- 
ing the position of the young in the pouches, and also the 
contracted condition of the sphincter at the external orifice 
of the sexual organs, I remained satisfied that this could not be 
the case, and that the young which Mr. Jackson found so lively 
after putting them in a bucket of salt water had then for the 
first time come into free contact with the element in which they 
were soon to live; but at the same time it can hardly be doubted 
that the water penetrates into the marsupial sac, since these 
young have fully developed gills. The size of the young com- 
pared with that of the mother is very remarkable, being full one- 
third its length in the one, and nearly so in the other species. 
Indeed these young Embiotoce, not yet hatched, are three or 
