Joseph Marshall Flint 433 
practically unchanged, save in the enlargement and differentiation of 
the lobules brought about by an increase in the ramifications of the intra- 
lobular ducts and consequent increase in the number of alveoli. Pari 
passu with these changes the Aa. intralobulares have undergone a numeri- 
cal increase corresponding 
to the division of the intra- 
lobular ducts. The capsular 
plexus is now very well 
marked. Arteries in the 
connective tissue surround- 
ing the gland, run to the 
capsule, forming there an 
irregular polygonal plexus 
which breaks up into capil- 
laries that pass irregularly 
in the outer layer of fibrous 
tissue that composes Ait Fra. 8. Submaxillary gland of pig’s embryo 24 centi- 
= 5 Z meters long. X 10 diameters. Aa. principales, inter- 
These capillaries reunite lobulares, sublobulares, lobulares, and intralobulares 
into venules which flow into 
venze comites that accom- 
pany the arteries forming a 
capillary plexus. As in the 
are now distinctly seen. The lobules have increased 
somewhat in size and the lobular veins and the venae 
sublobulares, interiobulares, principales are well 
formed. The plexus about the duct is not injected, 
arteries appear tubular and glistening while the veins 
are brownish and collapsed. The photographs from 
Figs. 5 to 8 are given their stereoscopic eflect by 
painting the back of the slides with India ink and 
focusing a strong light on the cut surface of the 
glands. They were then photographed with a Zeiss 
earlier stages, perforating apparatus with the above result. 
branches from the lobules 
and septal arteries run up and join this plexus. 
j LITERATURE. 
The only investigations on the blood supply of the submaxillary are 
those of Kowalewsky,’ who described the blood supply and drew from the 
arrangement of the vessels certain conclusions concerning the secretion 
of the gland, depending upon the anatomical relations of the vascular 
system to the cells and the lymphatics. Kowalewsky worked upon the 
parotid and submaxillary of the cat and dog. He believed many in- 
structive ideas could be gained from the different resistances of the vas- 
cular stream in different parts of the blood system as shown by complete 
and partial injections. His description is taken from the submaxillary 
gland of the cat. Both the arteria carotis communis and the vena jugu- 
laris externa were used for injection. An incomplete injection from the 
arterial side filled the capillary plexus in the walls of the ducts, while 
6 Kowalewsky, Arch. f. Anat. u. Phys. Anat. Abth., 1885. 
