DR. MARTIN BARRY ON THE CORPUSCLES OF THE BLOOD. 
249 
Fig. 83. Outline of blood-corpuscles from the egg of the Duck, incubated about 
12 days. 
Fig. 84. Blood-corpuscles, chiefly in outline, from the same egg. They are appa- 
rently in a stage more advanced than those in the preceding figure, 
with which, however, they were mixed. A nucleus, composed of discs, 
has been represented in some of these ; and in one of the corpuscles, 
discs are seen surrounding the nucleus. 
PLATE XXI. 
Fig. 85. Tadpole, about 5'". From the tail. Outline of epithelium-tables, having 
essentially the same appearance as blood-corpuscles circulating in the 
vessels of this larva. The peripheral portion of the six-sided tables 
resembled that of the object fig. 89. 
Fig. 86. Tadpoles, about .5"'. Epithelium-tables, from the tail, a, j3. Removed from 
the lacerated edge of the tail, a Is in outline. The form and size 
are here seen to have been very much the same as those of the blood- 
corpuscle in this larva. The same remark applies to the interior of 
this object, which is not shown in the figure. The envelope was also 
membranous. (3. The germinal vesicle-like nucleus eccentric, and 
scarcely coloured: the discs on the nucleus, blood-red. The other 
objects in this figure were seen in situ, y Resembled /3, but it was 
membranous at the surface. £, S, s, £, Resembled the ovum in their in- 
terior, and were blood-red at the surface. 
Fig. 8/. Tadpole, about 5"'. From the tail. Outline of the appearance presented 
by an epithelium-table undergoing division. (Dilute spirit.) 
Fig. 88. Tadpole, 6'". From the tail. Outline of three stages in the reproduction 
of epithelium-tables, having a situation corresponding to that of the 
large objects (centres) connected with pigment ramifications in figs. 90 
and 91. The object on the left hand (in fig. 88.) represents the earliest, 
and that on the right the most advanced, of these three stages. These 
tables propagate by division, like every other disc. Each of the objects 
in this figure consisted of two parts ; of which a was dark, — the other, 
(3, colourless and pellucid, a. Oldest and largest tables ; (3, newest 
and smallest tables, — mere discs. In the centre of (3, in the largest 
object, there was seen a part still more pellucid. f3 Is not in the 
centre of the object, but on one side. This corresponds with the situa- 
tion of the most essential part in all other discs. In some instances, 
the number of parts into which objects such as those in the present 
figure were dividing, was observed to be four ; this having been a stage 
still earlier. 
