116 DR W. B. DRUMMOND. 
The Spleen, which was at one time credited with being an 
active blood-forming organ, is now generally believed to 
play an important part in the destruction of red corpuscles. 
Quite recently a good deal of attention has been attracted 
by certain small glands, which appear to perform this office 
even more actively than the spleen. These are the 
hemolymph glands, and to them we must now turn our 
attention. _ 
The Hemolymph Glands were discovered in 1884 by 
Heneage Gibbes, who gave a brief description of them. No 
further observations were made upon them till six years 
later, when W. F. Robertson discovered them again and made 
the first detailed description of them. His observations were 
made chiefly on glands obtained from the sheep and bullock, 
where they are very abundant. Some specimens were ob- 
tained from the human subject, but were not in a sufficiently 
good state of preservation for microscopical work. Robertson 
suggested that the glands were concerned in the formation 
of red corpuscles, though he admitted that he could find no 
positive proof of this. 
Clarkson, in 1891, and again, in his Text Book of 
Histology, in 1896, added some fresh points to the descrip- 
tion of the hemolymph glands, and declared that there was 
little doubt that they were local centres for the production 
of blood corpuscles, both white and red. This statement, 
however, he did not substantiate by any observation tending 
to prove it, and it must be regarded as quite hypothetical. 
In 1897 Vincent and Harrison published a much more 
detailed account of the glands than had hitherto appeared, 
and pointed out reasons for believing that they took part, 
not in the formation, but in the destruction of the red 
corpuscles. 
This view was further supported by myself in an article 
published in 1900, in which the structure of the glands in 
several animals is detailed. 
Finally, in the present year Warthin has published a pre- 
liminary report on the structure of hemolymph glands found 
in the human subject in various pathological conditions. 
The hemolymph glands are small bodies which are found 
most abundantly in the prevertebral region of certain mam- 
