Hence it seems to me that such peculiarities and conditions as well 
as the other factors discussed by the writer in the articles referred 
to are probably responsible for the frequent occurrence of reddened 
lymph nodes in dogs and cats and hence for much of the confusion 
and the contradictory statements made by various investigators. 
The conclusion regarding the absence of hemal nodes in cats and 
dogs also holds for guinea pigs, rats and rabbits. As already stated 
only a small number of animals of each of there species were examined 
but from this examination I am completely at a loss to account for 
Lewis’s statement that the presence of lymphatic vessels cannot be 
demonstrated in what he regarded as hemal nodes in the rat. These, 
I take it, were nothing but reddened lymph nodes but since I did 
not examine a large number of rats it is possible, of course, that 
Lewis may have noticed nodes which were absent in the animals 
examined by me. However, this assumption would seem to be con- 
tradicted by Drummonn’s statement that the small hemolymph nodes 
present in the rat are very constant in position. Moreover, Lrwis’s 
statement regarding the relation of the lymphatics to what he considered 
hemal nodes in rats reminds one of a similar statement made by 
Drummonp concerning dogs. Drummoxp said that he tried injections 
on dogs but that he could not distinguish haemolymph from lymph 
glands. The reason is, of course, plain. They can not be distinguished 
because what Drummonp, Lewis and others regarded as hemolymph 
nodes are not true hemal nodes but lymph nodes containing erythro- 
cytes in the parenchyma and sinuses. Hence the results of injections 
into these and into lymph nodes must of necessity be the same. 
Consequently because of these and similar considerations and from 
personal observations and experiments the conclusion that hemal nodes 
do not exist in these animals seems abundantly justified. 
References. 
1. Baum, Können Lymphgefäße direkt in Venen einmiinden? Anat, Anz., 
Bd. 39, 1911. 
2, CLARKSoN, Report on hemal glands. Brit. med. Jr. Vol. 2, 1891. 
3. —, A textbook of Histology. Saunders Phil. 1896. 
4. Dayton, Haemolymph nodes. Am. Jr. Med. Sci. Vol. 131, 1904. 
5. Drummonp, On the structure and function of haemolymph glands. Jr. of 
Anat. and Phys. Lond. Vol. 34, 1900. 
