rr 
IG, Dalton, Jr., on the Proteus anguinus. 391 
They can be easily found almost unaltered in the blood vessels, 
aud particularly in those of the gills, even in specimens which 
ve been kept for a long time in spirit. ‘They are of a flattened 
oval shape, like those of the frog, with a central, white, granular, 
roundish nucleus, also somewhat flattened. The length of the 
globules varied, in the specimen examined, from -0016 to -0023 
nen. ‘The breadth is usually -0013, and the thickness -00U3, 
As this last measurement is exactly the diameter of the human 
blood globule, some estimate may be made of the difference be-~ 
tween them. In fig. 4 the blood globules of human blood, of 
the frog, and of the Proteus (a, b, and c) are magnified in the 
Same proportion, in order to show their relative sizes. The mus- 
cular fibres of the body are also very large, and very distinctly 
Stiated. T'heir diameter varies from ‘0019 to ‘0036 inch. The 
herve-fibres were not remarkably large, those from the facial 
measuring only -00027 inch in diameter. 
The two most interesting peculiarities of the animal, taken in 
Connexion with its subterranean mode of life, are. the colorless 
condition of its skin, and the imperfect development of its visual 
organs. At first, the eyes seem to be altogether wanting; but 
on close examination, they may be discovered, in the recent state, 
% two minute blackish points, situated about the junction of the 
anterior and middle thirds of the head (fig. 1). When the ani- 
mal has been preserved in spirits, it is sometimes impossible to 
distinguish them until the integuments have been removed. 
Y are then found lying immediately beneath the skin, imbed- 
In a small quantity of adipose tissue (fig. 2). In an individ- 
ual Measuring 82 inches in length, the eyeball was ;,th of an 
a in diameter; and the optic nerve, just before joining the 
» stsnd of aninch. Notwithstanding its minute size, how- 
ret, the eye is sufficiently well developed as to its structure. 
The sclerotic is covered with brownish spots, mostly hexagonal 
shape, and which are more thickly crowded and deeper in 
“lade just at the margin of the cornea, where they form 2 cca 
ish ring (fig. 3), The crystalline lens is globular, and risth o 
at inch in diameter. There were some appearances of a nearly 
Pétison with the size of the animal, and in having a somewhat , 
7 oe fr 
