14 
HEMOLYMPH NODES OF THE SHEEP 
both carotids and jugulars by severing all the ventral soft parts of the 
neck, the nodes were always found turgescent. If death occurred with- 
out bleeding, there was no marked difference save that the veins draining 
the nodes seemed a trifle fuller, and the color of the nodes a little darker ; 
which latter fact may perhaps be accounted for by defective aeration of 
the blood during death. This failure of hemolymph nodes to become 
paler during death by bleeding stands in striking contrast to what is 
noticed in many lymph nodes, v Schumacher [27] also emphasized the 
effect of bleeding upon the color of lymph nodes and pointed out that 
lymph nodes in foetuses in which free bleeding is secured by severing the 
cord, are always much paler than those in foetuses which are killed 
without such bleeding. The significance of these differences in behavior 
between hemolymph and lymph nodes will be discussed in connection with 
the circulatory condition in the nodes. 
Since the vein draining a node is usually dilated with blood, it can 
frequently be seen without difficulty on inspection. In almost any car- 
cass one or two nodes can be found the veins of which are plainly visible 
from five to ten centimeters or more from the node, even if the latter 
is only a few millimeters in size. Anastomoses with the veins from 
adjacent nodes are quite common. The artery, on the contrary, is not 
seen on inspection alone, no matter how turgescent or large the node, 
or how prominent the vein. Pressure upon the nodes generally results 
in rupture, without visibly dilating the vein or the artery or decreasing 
the vascularity of the node. This inability to force out the blood by 
means of external pressure on the nodes was quite puzzling, until the 
peculiarities of their structure supplied an explanation. 
Lymphatic and Vascular Relations 
Lymphatic vessels were never detected or dissected out in the hilus 
of a hemolymph node however large, although it was often an easy 
matter to see and find them near a lymphatic node of much smaller size. 
Frequently lymphatic vessels of varying calibre and conspicuousness 
could be seen near hemolymph nodes, or even in contact with them ; but 
even in the case of very large nodes no communication was ever noticed 
between them and the nodes, upon the most careful examination. Hence 
these observations confirm the conclusion of Weidenreich [37] in this 
regard and contradict Helly's [11] statement to the effect that lymphatic 
channels can be seen to enter the hilus of the hemolymph nodes, although 
not found within the node, and that nodes which lie near large lymphatics 
contain such vessels. Aside from the difficulty, or impossibility even, 
