MONTANA EXPERIMENT STATION. 205 



more than two together. A single egg is shown at plate I (figure i). 

 They are usually oval in outline, some being circular or nearly so, 

 and they measure slightly over one mm. in length, including the flat 

 outer rim by which they are attached to the leaf. The}^ are trans- 

 lucent and almost colorless at first, but as the embryo develops the 

 black head and thoracic shield of the larva show through and the 

 outline of the curled larva may be distinctly seen. The egg shell 

 reflects the prismatic colors, both before and after the larva emerges. 



^^'e have aboVe called attention to the close resemblance between 

 the adult of the bud moth and that of the codling moth. It is. even 

 more difficult to distinguish between the eggs of the tAvo species. In 

 size, shape and general appearance, they are very similar. They are 

 laid in precisely the same position on the foliage and are deposited at 

 the same time. They both reflect light and show irridescence alike, 

 and both are translucent. I know of no way to distinguish between 

 the two except by the difl^erence in the character of the surface of 

 the shell of the egg. 



The hatching of the egg takes place in from six to ten days after 

 being laid, and, issuing from the egg, the larva makes a hole 

 through the edge of the central portion and crawls forth. This cater- 

 pillar is greenish In color, very small and delicate and it at once sets 

 about making a place of retreat and protection. Passing to the un- 

 der side of the leaf it constructs a very small silken tube near the 

 mid rib and usually towards the base of the leaf. The larva feeds 

 from the epidermis and middle layers of cells leaving the opposite 

 epidermis unbroken. The castings of the larva are built into the 

 tube giving it a black color. The portion of the leaf from which the 

 larva feeds is covered with silken threads laid down by the larva 

 and whenever possilde a near-by leaf is drawn up and fastened to 

 the first leaf by the silken threads. Thus one often finds two leaves 

 stuck together, and, in pulling them apart, finds the little black tube 

 of this insect. The larva will not be seen unless forced to crawl out. 



In selecting a place in which to construct a home the larva 

 searches for two leaves that are near enough together to be easily 

 brought in contact. 



In the manner here indicated the larvae continues to feed until some 

 time in September, when, apparently prompted by instinct they 



