THE PECAItf NUT CASE-BEAKER 3 



He further states : 



I have myself found the larval cases of a Phycitid in southern New Jersey 

 on a large-leaved oak, which may be the cases of this species. They were horn- 

 like, much resembling those of indigenella. The larva turned over the edge of 

 the large leaf binding the edges, and forming a habitation large enough to move 

 about freely within. The case itself was fastened within with threads of silk. 



The habitat given by Hulst is New Jersey and Texas, but there is 

 no mention of the food plant for the material from Texas, which was 

 probably taken on the pecan. In the writer's opinion, the record 

 of the New Jersey specimen "from oak ,; is very doubtful, because 

 the description of the cocoon and the manner of pupation do not 

 coincide with the facts regarding Acrobasis hebescelta as determined 

 in an extensive study of this species. 



CHARACTER OF INJURY 



The larvae of the pecan nut case-bearer may attack either the tender 

 shoots or the immature nuts. The larvae that pass the winter in 

 hibernacula around the buds, cause damage in early spring by attack- 

 ing the tender shoots, in which they tunnel and eat out the interior, 

 leaving the outside intact. Many of the attacked shoots wilt and 

 turn brown, and others are broken off by the winds (PL IV) . Such 

 injury is not very serious, compared with the damage caused by the 

 first and second brood larvae, which confine their attacks to young 

 green nuts. 



During May the first-brood larvae make their appearance and bore 

 into the recently set nuts. At the point of attack pellets of frass 

 or borings are cast out (PL II) and held together by means of fine 

 silken threads that form a short silk-lined tube. Nuts injured by 

 this insect always show the characteristic mass of frass protruding 

 from the place where the larvae gained entrance, which is invariably 

 in the side of the nut near the basal end. The larvae of the second 

 generation attack the nuts in the same manner as those of the first 

 generation, but the damage to the crop is not so extensive because 

 of the size of the nuts at the time of attack (PL III) . Early in the 

 season a single larva may destroy several nuts before attaining full 

 growth, while later in the season one or two nuts seem to be suf- 

 ficient for its subsistence. The writer's observations show that by 

 far the greatest damage to the nut crop is inflicted by the larvae of 

 the first generation. 



The larvae of the third generation, which make their appearance 

 in the late summer, usually feed very little. They seem to prefer 

 the shucks or hulls, in which they gnaw only through the surface, 

 forming small, narrow, elongated tunnels of frass particles of a rather 

 delicate or flimsy texture. Such injury does not interfere with the 

 normal development of the nuts. Some of these larvae also feed 

 slightly on the leaf petioles and succulent shoots, but the damage 

 thus caused is insignificant. When the larvae of this generation 

 seek hibernation quarters they are usually a little less than one-tenth 

 of an inch long. 



DESCRIPTION 



EGG 



The egg (PL I, A) is elliptical, convex above and flattened below, 

 with the surface finely wrinkled. When first deposited the egg 

 is greenish white, and as incubation advances it takes on a reddish 



