504 EMBRYOLOGY OF THE TURTLE: Part III. 
The consistency of the fresh albumen of Turtles’ eggs is much greater than 
in Birds; so much so that the shell and shell membrane may be stripped off, if 
removed before absorption is far advanced and the yolk and surrounding  glairy 
envelope remain unchanged, and may even be taken up in the hand without  sus- 
taining any injury. It is also a very easy matter to strip off several layers, one 
after the other, even down to within one or two strata, or sometimes to the very 
last, which lies close to the yolk, without disturbing the latter in the least; in 
fact, these innermost layers of albumen seem to have considerably more consistency 
than those exterior to them." 
Upon making a transverse section of the thickness of the albumen, the edge 
of the cut presents the appearance of several concentric layers divided by dark 
lines; the distance of the latter from each other, and consequently the thickness 
of the former, varying according to the region of the mass to which they belong. 
If in a round egg, (Pl 9b, fig. 6,) the strata (a) are equal throughout; but in an 
the ends of the egg, 
oval one (Pl. 9b, fig. 3) they are thickest near (a,) and 
eradually thin toward the shorter axis, (e,) at which point they attain to the 
minimum of thickness. Their number seems to vary according to the species ; 
for instance, in Chrysemys picta there are six or seven, in Cmosternum pennsylva- 
nicum about ten, and in Platypeltis ferox ten, ete. Further research is needed to 
ascertain how constant these numbers are in different species. Each stratum is com- 
posed of a clear, glairy albumen, in which minute, highly refracting, granular bodies 
of a more or less oval shape are densely packed and arranged in lines (PI. 9b, 
fig, 
of the layers, approach each other, so that finally contact ensues between them ; 
3a, 6a); and these lines, as they are successively nearer and nearer the borders 
and hence their combination produces the dark zones. It is at these dark zones 
that the layers of albumen separate when peeled off Where the strata grow 
thin, in oval eggs 
gos, the lines of granular bodies are closer together, (Pl. 9b, fig. 
3a, 6a,) throughout the thickness of the layer, than elsewhere. It is further 
remarkable, that in oval eggs the albumen may be pulled off in layers transverse 
to the long diameter more readily than otherwise. Perhaps this is owing to the 
uniformity of its density in that direction, whereas it constantly changes toward 
the projecting ends of the eve. 
When the albumen begins to be absorbed into the yolk sac, these strata are 
1 The above statements may be most fully sus- 
tained by opening the eggs of Chelydra serpentina, 
Ozotheca odorata, Cinosternum pennsylvanicum, Na- 
nemys guttata, Chrysemys picta, Glyptemys insculpta, 
and Cistudo yirginea. We have not examined so 
closely our Western and Southern species in this re- 
spect, nor have we made any experiments respecting 
the temperature at which the albumen of Turtles co- 
agulates; but would take this opportunity to refer to 
the interesting paper of Messrs. Valenciennes and 
Fremy upon the physical and chemical properties of 
the Turtle’s egg. 
Comptes-Rendus, 1804, vol. 38. 
