438 



INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



best experts. The second spraying should follow the first by three 

 or four weeks. It is a common practice to combine Bordeaux mixture 

 with both of these sprays as a control measure for scab. 



Fig. 446. — Adult female of the codlin-moth, Cydia pomonella 

 (Linn.). Enlarged four times. (Original) 



Natural Enemies. — So far natural control of the codlin-moth has 

 proven very unsatisfactory. Through Mr. George Compere the State 

 has secured a hymenopterous parasite (CaUiephialtcs messor), which 

 preys upon the larva? just after the cocoons are spun. This parasite 

 has never been able to accomplish any satisfactory results and is no 

 longer being propagated as a natural means of control. 



THE FRUIT-TREE LEAF-ROLLER 30 



Archips argyrospila Walker (Family Tortricidae ) 



(Fig. 447) 



Description. — The prevailing color of the moths is a rusty brown, 

 varying from light to rather dark, with a prominent light spot on 

 the margin near the middle of the front wings and other spots irregu- 

 larly arranged. With wings closed the length is from | inch to ^ inch. 

 The wing expanse is from ^ to 1 inch. The eggs are laid in masses 

 of from ten to one hundred and fifty and are covered with a sticky 

 substance which hardens and protects them during the winter. The 

 masses are very flat and somewhat circular, the diameter varying from 

 W inch for the larger to } inch for the smaller. (Fig. 447.) "When first 

 deposited they are greenish-yellow, but become gray or almost black 

 by winter, and many turn gray in the spring shortly before hatching. 

 Hatched eggs are distinguished by the small holes in the surface. The 

 caterpillars when first hatched are about ^ inch long and light yellow. 

 They later become deep green with the head and thorax shiny brown 

 or black. When full-grown they measure about § inch in length. The 

 pupae are dark brown. 



Life History. — The winter is passed in the egg stage upon the 

 trunks and limbs of the host trees, fences, or in fact almost any place, 



31 °Weldon, G. P., Mo. Bui. Cal. Hort. Com.. Vol. IT. pp. 637-647. 1913. 

 Gill, T. B., Bui. No. 116, pt. V, Bur. Bnt. U. S. Dept. Agric, 1913. 



