42 CELLULAR STRUCTURE OF THE RED BLOOD-CORPUSCLES. 
drop where the liquor sanguinis has become most concen¬ 
trated will be frequently discovered to contain one, two, or 
more crystals; and under the most favorable circumstances 
of temperature and hygroscopic condition of the surrounding 
air, I have seen this process of crystallization go on until 
the contents of almost every corpuscle assumes the crystal¬ 
line form, either wholly or in part, the cell wall being left 
in the former case perfectly colourless and transparent. 
The effect of these crystals as they gradually elongate is 
very remarkable and interesting, being precisely that which 
would be produced by sticks of similar shape contained 
within an ordinary bladder partly filled with fluid ; thus, for 
example, I have several times seen a single crystal, as if in¬ 
creased in length, thrust out the ends of the oval corpuscle, 
until the conjugate diameter of the cell became one third 
greater, while its transverse dimension diminished to less than 
half its original magnitude, the nucleus being compressed 
closely against the side of the prism. Or in cases where one 
or more crystals happened to lie across the long axis, that 
decreased until the whole corpuscle assumed a lozenge-shaped 
or rectangular form, as in a very perfect specimen which I 
have mounted dry, the folded edge of whose capsular mem¬ 
brane may be seen supported by the crystals, like a washer¬ 
woman's clothes-line upon its prop. 
It may in the first place be objected to this demonstration, 
that the appearance which it affords of a plicated membrane 
around the extremities of the crystals is caused by partial 
desiccation of the surface of the corpuscle while the speci¬ 
men was being prepared; that such cannot, however, be the 
case, is proved by the fact that if, to blood freshly drawn 
from the reptile upon a slide, water is added, beneath the 
microscope we can produce an exosmosis of the coloured 
material into the diluted liquor sanguinis, leaving the same 
transparent ceil wall, which becomes visible when the cell 
1 contents are crystallised within it; and it is obvious that 
a membranous envelope, which is equally distinct under the 
opposite states of dryness and moisture, cannot be considered 
the result of either condition. Again, perhaps it will be as¬ 
serted, secondly, that the appearances here presented might 
be simply the result of partial crystallisation in such a drop 
of viscid material as Professors Flint and Beale consider the 
red blood disks, which drop, if the process were complete, 
'would have entirely assumed the crystalline form; but I 
think I can quite destroy the force of that or any similar 
argument by the aid of other mounted preparations, some of 
them showing that well-developed crystals, which happen to 
