The Codling-Moth, 105 



otherwise, we should oftener find more than one worm in the same 

 apple " (Le Baron). We have often seen two eggs on an apple no 

 larger than the one shown at a in figure 131, and in one case we found 

 five egg shells, or, perhaps, sterile eggs (as we found no worms in the 

 fruit) on such an apple. Koebele counted 1 1 eggs on a pear in Cali- 

 fornia in August. 



Mortality ainong the eggs. — Our observations agree with those of 

 Washburn, Goethe and Card that many apparendy sterile eggs are 

 laid by codling-moths. 



Duration of the egg-stage. — Rocsel stated in 1746 that the eggs 

 hatched in eight days. Later observers record a variation of from 

 four to ten days. The eggs under our observation hatched in about a 

 week, and this is doubtless about the usual duration of this stage, 



A day or two after the ^'g% is laid, a narrow whitish or yellowish ring 

 can be plainly seen through the shell. A day or so later this ring takes 

 on a decided reddish tinge ; it is visible in the picture of an egg at e in 

 figure 131. Soon after this the black head of the developing caterpillar 

 and the outline of its body can be plainly seen. At // in figure 13 1 is shown 

 an egg with the little caterpillar almost ready to emerge. 



The Young Apple-worm and its Habits. 



How it gets out of the egg and its characteristics. — Roesel tells us in 

 I 746 that the little caterpillar " comes out of that part of the egg where 

 it lies on the fruit, so that the very small opening may not be observed, 

 because it is yet covered by the egg-shell which still adheres." We find 

 no other hint in the literature on this point until Washburn observed 

 in 1892 that the young worms "broke or ate their way through the 

 shell and entered the apple somewhere else than at the spot occu- 

 pied by the egg." A caterpillar which we saw emerge, came out of 

 the egg near the edge at one end. In the picture of an egg-shell at 

 es and es in figure 131, one can see at the upper end a small black 

 spot, and extending from this to the right is an irregular, whitish line, 

 which was the crack made by the worm when it pushed its way out. 



A newly-hatched apple- worm measures scarcely a sixteenth of an inch in 

 length, and is of a semi-transparent whitish color, with a shiny black head 

 and blackish thoracic and anal shields. Usually the body is marked with 



