66 U.S. NATIONAL MUSEUM BULLETIN 255 



the oviposition site most frequently ranges from 4 to 7 mm. 

 Prior to egg insertion, the female assumes a transverse position across 

 the upper surface of a branch (fig. 33), in sharp contrast to the vertical 

 or lengthwise position that is characteristic for Prodoxus and probably 

 Agavenema. She then bends her abdomen under her body and around 

 the stem and commences to scrape a small pit in the plant tissue. 

 During this operation, the movements of the abdomen are quite 

 forceful, whUe the foreportion of the moth's body remains relatively 

 motionless. Digging is accomplished primarily through a series of 

 lateral or sideway movements of the abdomen, interspersed with 

 irregular, circular motions. Little or no plant tissue actually is 

 removed from the egg pit in the sense of a true excavation; instead, 

 the tissue is merely torn and pushed aside by the ovipositor. After 

 the pit has been excavated to a depth of about 0.5 to 1.0 mm, an egg 

 is deposited in the cavity. Sometimes the egg is placed as deep as 

 0.5 to 0.7 mm below the surface of the stem, but frequently the pit 

 is more shallow, thus exposing the top of the egg. Immediately 

 following the insertion of an egg in this manner, the moth then steps 

 sideways slightly and commences, without interruption, to dig 

 another pit alongside the first. This procedure is repeated normally 

 until a row of tiny pits has been excavated, each pit being separated 

 by a distance not greater than 1 mm. As mentioned earlier, when 

 the eggs are deposited in a lateral branch, they are always placed on 

 the lower side; however, the exact location often is not along the mid- 

 dorsal line of the stem, but instead, slightly up one side in the direc- 

 tion of the moth's abdomen. Also, the angle of egg insertion usually 

 is not along the radius of the stem, but is slanted at a slight angle to 

 the stem's surface. 



The egg (fig. 36) is broadly oval in shape (in sharp contrast to that 

 of Prodoxus and, particularly, Tegeticula), of an opaque, greenish- 

 white color, and approximately 0.2 to 0.4 mm in length. Its width 

 is usually about one-half its length. As is true for most Lepidoptera 

 eggs that are inserted into plant tissue, the eggs of P. pollenifera 

 quickly desiccate if completely exposed due to the presence of a very 

 thin and membranous chorion. 



Considering the effort necessary for P. pollenifera to accomplish 

 oviposition, one would expect the length of time requu-ed for this act 

 to be considerable. In two instances the amount of time consumed 

 during egg laying was noted. In both cases the females were in the 

 process of ovipositing when fii'st observed; thus, the total length of 

 time that elapsed between when they first commenced to lay eggs at the 

 particular site to the time they ceased, is not known. At no time did 

 the moths interrupt their egg laying movements except to move 

 slightly sideways in order to begin the next egg pit. It was also noted 



