ITS DIFFERENT PHASES OF DEVELOPMENT IN THE ANIMAL SERIES. 
81 
in the earlier part of the stage of coloration, — all identical with the corresponding 
corpuscles of the blood of the animal. 
The Corpuscle of the Lymph of the Frog. 
103. The lymph subjected to examination was obtained from one of the posterior 
lymph hearts. The corpuscles were, — 1 st. Corpuscles at once recognisable as identical 
with the granule-cells of the blood of the animal, and these in both coarsely and finely 
granular stages. There were also cells in transition from granule to nucleated 
cells. 2 nd. Corpuscles which at first sight appeared to be free nuclei, but were dis- 
covered on closer examination to be inclosed within cells of a circular or oval form, 
and extremely pale. The identity of these cells with the nucleated cells, uncoloured 
stage, of the blood of the animal could not be overlooked. 3rd. A considerable num- 
ber of red nucleated cells, the same as the “ red corpuscles” of the blood. Many of 
these no doubt were derived from small blood-vessels which had been cut in opening 
the lymph heart, but some of them I am inclined to believe belonged to the contents 
of the lymph heart, those especially which appeared to be in an early stage of colora- 
tion. (See the figures of the blood of the Frog.) 
The Corpuscle of the Lymph of the Common Fowl. 
104. The lymph subjected to examination was obtained from a lymphatic gland. 
It contained, — 1 st. Corpuscles about 3 -^oth of an inch in diameter, less or more, iden- 
tical with the granule-cells of the blood of the same animal ; some being in coarsely 
and some in finely granular stages (figs. 1 to 2 .). 2 nd. Corpuscles in much greater 
number than the preceding', of the form of circular discs, with a depressed point in 
the centre about 7 (mo th of an inch in diameter, and though colourless very distinct. 
At first glance these corpuscles appeared to be free, but subjected to more careful 
examination, they were observed to be contained within a cell of a diameter of about 
3000 th of an inch, the wall of which was extremely pale. Having once perceived it, 
however, there was no difficulty in recognising the whole as a nucleated cell identical 
with the nucleated cell of the blood of the animal, in its uncoloured stage (fig. 3 .). 
There were some nucleated cells similar to those just noticed, but slightly tinged red 
in the interior; and besides such there were some oval nucleated cells, altogether 
similar to the oval red corpuscles of the blood of the animal, but coloured only, and 
that slightly in the interior, the circumferential doubling of the cell-wall appearing* 
quite transparent and colourless. 
The Corpuscle of the Lymph of Man and the Mammfera. 
105. The description of the corpuscles of the lymph, here to be given, was drawn 
from the examination of those presented by the contents of the thoracic duct. Besides 
the contents of the thoracic duct of the human subject, I have also particularly 
examined the contents of the thoracic duct of the Rabbit, and found their corpuscles 
to be in all essential respects identical. 
m 2 
