204 
tical shape, about one-third the size of the human blood-corpuscle; but, 
as the skin of the reptile is abundantly covered with slimy mucus, it 
is probable that in taking the blood (a very small quantity of which 
was obtained) the mucus was mixed with it, and produced these 
vesicles, which differ from any that I have seen in the blood of other 
reptiles. 
With the blood of the Salamander I examined that of the Water- 
newt (7'. cristatus) and that of the Common Frog (R. temporaria), 
both reptiles being alive. The drawings of the corpuscles which 
I exhibit will give the relative sizes; they are all magnified 500 
diameters. I have also added a drawing of the human blood-cor- 
puscle, by way of comparison. In these illustrations the largest cor- 
puscles, which are far more numerous than the others, have been 
selected. 
They measure as follows :— 
Fractions of 
inch in 
—— 
Blood-corpuscle of Man ............. ees so: 
Z ; — diameter. on i pers ai 
Blood-corpuscle of Sieboldia ........ giv tOzdy =a tO st 
1 2. 
Nucleus of same s73e0 50 S202 a gg | eee 
, , 1 1 
Blood-corpuscle of Triton cristatus ........ stu. OTe 0° 
Blood-corpuscle of Rana temporaria ...... rss) oo 
The most interesting and important circumstance connected with 
this examination, is that this Salamander, a non-perennibranchiate* 
reptile (as I believe), probably has a blood-corpuscle as large, or 
nearly as large, as the Proteus and Siren, reptiles which retain their 
gills. 
In the excellent and original papers by Mr. Gulliver in our ‘ Pro- 
ceedings’ for 1845 and other years, ‘‘ On the size of the Red Cor- 
puscles of the Blood in the Vertebrata,” that gentleman infers that, 
* although there is no relation between the size of the corpuscle and 
that of the animal in different orders, in the same order the largest 
species have generally larger corpuscles than the smallest species. 
Thus in the large Ruminants the corpuscles are distinctly larger 
than in the smaller; and the same fact is observable in the Rodents. 
In these examples the gradation in the size of the corpuscles may 
not exactly follow that of the animals; but none of the very small 
species have corpuscles so large as those of the largest species.” 
The examination of the blood of this reptile is probably another 
confirmation of the general correctness of Mr. Gulliver’s opinion ; 
but in my examination of the blood-corpuscles of a great many species 
of vertebrate animals I have found several deviations from this law, 
more especially in the Ophidian reptiles and in the Osseous fishes ; 
among the Ruminants too, many of the smaller Antelopes have larger 
corpuscles than the Giraffe. In some of the Cervide the size of the 
corpuscle does not correspond to that of the animal. In the Ophidia 
* It has been shown by Van der Hoeven that the Sicholdia is a true Perenni- 
branchiate, although there is no gill-aperture present, or rather it has early dis- 
appeared. See his ‘ Zoology ’ (Clarke’s translatior), ii. 242.—P. L. S. 
