Cuap. II. ALBUMEN AND EGG SHELL. 505 
resorbed at the upper side of the ege, not from within outwards, but, on the 
contrary, the most exterior ones first, and successively those more interior; each 
one, the moment it is perforated, by the loss of its substance at the point of 
resorption, shrinks away centrifugally, thus allowing the vitellus to rise gradually, 
till it finally touches the shell. In this condition, the strata appear as if cut 
across obliquely. 
But let us return, and look a little more closely at the structure of this por- 
tion of the egg. Upon peeling off three or four strata, and viewing them per- 
pendicularly to their surface, we instantly see that the dark lines mentioned above 
are the profiles of so many layers of oval granular bodies, and, more remarkable still, 
that the longer axis of all the oval bodies in one layer trend in the same direc- 
tion (Pl. 9b, fig. 6b, a); whilst the longer axis of those in the next exterior or 
interior layer, although running parallel to each other, yet have a different direc- 
tion from the last, running either at right angles, (fig. 6b, 2,) or at thirty degrees, 
or with more or less divergence, from them (fig. 6b, ¢). This peculiarity holds good 
throughout the whole mass of the albumen; but it is not limited to this part of 
the egg. Before going further, we would point out the slightly nodular character 
of some of the oval granular bodies, which appear as if they were composed of 
two or three smaller ones. These bodies are very minute, comparatively, in some 
species, as in Glyptemys insculpta, but yet exhibit in their linear arrangement the 
same relation to each other in the different layers, as obtains in other species 
where they are much larger. 
Those layers of the shell membrane which lie innermost and in contact with 
the albumen, hardly have a tenacity superior to the inner strata of the latter. 
This will not seem surprising when the structure of the two is compared, for 
then we find that they are scarcely to be distinguished from each other. The 
only difference noticeable is, that the granular bodies of the shell membrane 
are more elongated, and that each granule seems to be composed of a greater 
number of smaller granules than obtains in those of the albumen (PL 9b, fig. 6c). 
As in the latter, so also in the shell membrane, the granules of the different lay- 
ers run in diverse directions, but parallel in the same layer. The distance of these 
layers from each other is almost nothing, just as is the case among the closest 
layers of the albumen; but, as there, an excessively hyaline granular film of albu- 
minous matter fills up the interspaces. 
Proceeding a little further outward, the oval granules of each layer approxi- 
mate each other, and lie in contact, end to end, thus forming beaded fibres (PI. 
9b, fig. 6d); those im one horizon crossmg those of another at various angles, as 
heretofore. Interspersed among them are minuter particles of various sizes and 
excessive faintness, imbedded in the albuminous film, and evidently arranged in 
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