CYPRESS BARK SCALE. 15 



themselves again. Although the legs are retained throughout the 

 full lifetime, they are of no further use to the female larva except 

 to aid in removing the cast skins when molting. 



Larvae will attach themselves on twigs as small as one-fourth inch 

 in diameter and on trunks a foot or more in diameter, provided the 

 bark is not too thick to be pierced with their proboscides. A few scale 

 insects have been found infesting the smooth trunk of seedlings less 

 than one-half inch in diameter, but rough bark is essential to a heavy 

 infestation. The deeper the larvae are able to go into the crevices the 

 more satisfied they appear to be, They have been found so well 

 secreted in crevices that it would seem there was no room left for 

 their future growth, and much less any chance of mating, particu- 

 larly after being enveloped with a white flocculent secretion. 



LARVA. 



FIEST INSTAR, 



Immediately after attachment the larva begins enveloping itself 

 with this white cotton until entirely hidden from view. A drop 

 of honeydew, resembling pitch, is emitted by some larvae, especially 

 on vigorous trees, during the first few weeks after attachment. 



Growth starts immediately after attachment and is practically 

 constant throughout the whole instar. The larva at the end of the 

 instar is very similar to those just hatched, except that the former 

 are larger, somewhat broader in proportion to their length, and 

 slightly darker in color. 



At the end of the first instar, the larva molts, the skin being pushed 

 down off the tip of the abdomen. From 40 to 44 days were required 

 to complete the first instar in the few cases observed^ 



SECOND INSTAE. 



There is very little development during the second stage. The 

 female larva secretes more waxy cotton and changes in size and shape 

 until it resembles the adult female. After a period of from one to 

 two months the second molt occurs and the larva becomes an im- 

 mature adult. 



The male larva increases in size and becomes yellowish white in 

 color. It takes on a firmer and trimmer appearance. After a slightly 

 shorter time than that required by the female larva, the male larva 

 detaches itself and crawls about in search of a favorable place in 

 which to pupate. It may pick a spot under some cotton or in a curl 

 of the outer bark. Cocoons have also been found in the cast skins of 

 coccinellid larvae and in the ruptured bodies of dead female scale 

 insects. 



