Lydia M. DeWitt 231
union of the duct which had apparently taken place when the
gland had been simply ligatured. In seven cases, after divid-
ing the gland between two ligatures at s, a fold of omentum
was drawn between the two ends and sewed or tied in place.
The animals lived after the operation from eighteen hours to
I97 days. Ten of them, on account of an acute inflammation
(three cases) or inanition (the cats often refused all food for
the first week or ten days after the operation), died too early
to hope for a sufficient degeneration of the gland tissue to attain
even an approximate isolation of the islands. The changes
found in the glandular parenchyma were much the same as those
described by Ssobolew. The larger ducts were much dilated
and filled with desquamated epithelial cells and detritus. The
smaller ducts and the acini could scarcely be differentiated, since
the gland cells had in the main early lost their differential stain-
ing power, the outer zone no longer taking the basic stain nor
the inner the acid stain, but both staining alike. The cells in
both small ducts and acini in many cases disappeared. The
membranæe propriæ then collapsed and appeared like strands
of connective tissue. The interlobular connective tissue was
greatly increased, so that the lobules were much compressed, but
still retained the appearance of lobules. In few, if any, of my
cases has the lobule been entirely replaced by connective tissue
except in the immediate neighborhood of the ligature, wh(re
often both gland tissue and areas of Langerhans had completely
disappeared to give place to new connective tissue. This was
especially the case in those animals in which the gland was
divided and cauterized.
In my earlier operations, no special effort was made to avoid
including the blood-vessel in the ligature and in some of these
cases islands as well as gland tissue had suffered atrophy. In
the other experiments, in which an effort was made to avoid
interference with the blood supply of the gland, the areas were
quite well preserved regardless of the extent of atrophy of the
gland tissue. In those animals killed during the first six weeks
or two months, however, many of the islands appeared smaller
and less numerous than normal, although no accurate counts