282 Prof. L. C. Miall and Mr. T. H. Taylor on the 
which the egg was passed into the leaf. There are two 
egg-envelopes, an external chorion, which is yellowish, 
finely pitted, and prone to adhere to the vessels of the 
midrib, and a transparent vitelline membrane. The head- 
end of the embryo is at first adjacent to the micropyle, 
and therefore points to the mouth of the passage, but 
before hatching the embryo reverses its position, as if to 
facilitate the «travelling of the larva along the vessels 
towards the apex of the leaf. 
Egg with unhatched larva taken from midrib of holly-leaf. (x 165.) 
In the fresh-hatched larva segmentation is already 
complete, and the mouth-parts are well developed. The 
fat-body, which contains the residue of the fat-globules of 
the egg, is scanty. The tracheal system is filled with air, 
but does not as yet open to the exterior. Numerous fine 
denticles are already developed on the surface of the body, 
The alimentary canal contains no solid food. 
Very little change in the appearance of the larva can 
be noted so long as it remains in the midrib; the fat- 
body enlarges, and the fat-globules become more numerous. 
