INJURIOUS AND BENEFICIAL INSECTS OF CALIFORNIA. 



429 



THE SQUASH-VINE BORER 



Melittia satyrimformia Hiibner (Family iEgeriidse)* 1 



(Trochilium eeto Westwood) 



(Melittia cucuriitw Harris) 



l Melittia pulchripes Walker) 



(Melittia amcena H. Edwards) 



(Pig. 437) 



Description. — The adults are beautiful clear-winged moths. The 

 head and thorax are dark, the abdomen is marked with orange or red 

 and black or bronze ; the fore wings are opaque, olive-brown with green 

 iridescence; the hind wings are transparent with black veins and olive 

 green or bronze fringe of hairs. The hind legs bear a large fringe of 

 hairs which is orange on the outer side and black on the inside. These 

 hairs are longer on the male than on the female. The wing expanse of 

 the females is about H inches and 1^ inches or less for the males. The 

 eggs are reddish-brown, oval, about ^ inch long and attached at the 

 side. The larva? or borers are white with dark brown head, robust, dis- 

 tinctly segmented and 1 inch long. The pupa? are shiny, dark red or 

 brownish, with horn or spine on head, many spines on abdomen and 4 

 inch long. They are 

 inclosed in dark 

 closely woven co- 

 coons and covered 

 with small soil parti- 

 cles from the resting 

 place in the earth. 



Life History. — 

 The winter is passed 

 in the pupal stage in 

 the soil. Adults be- 

 gin to emerge in 

 April and May and 

 to lay eggs upon the 

 larger stems near 

 the ground and all 

 other parts of the 

 food plants. A single 

 female may deposit several hundred egg's. The eggs hatch in about two 

 weeks and the larva 3 at once make burrows into the stems, some working 

 down into the roots while others burrow into the base and' woody parts 

 of the plants. White frass is forced from the tunnels by the feeding 

 larva?. It requires about one month for the larvae to become full-grown. 

 They then leave the plants and enter the soil near the bases to a depth 

 of about two inches, where the pupal cells are made, the eocoon con- 

 structed and pupation takes place. In from two to three weeks the 

 adults begin to emerge. The entire life cycle requires about two 

 months. The adults of the first generation appear in June and duly 

 and those of the second generation in August and September. There 

 are two broods a year. 



""'Smith, John B.. Bui. No. !)4, N. J. Agrcl. Exp. Sta., 1893. 

 Chittenden, F. H.. Circ. No. 38, Bur. Rnt. U. S. Dept. Agric, 1908. 

 Smith, R. I.. Bui. 205, X. C. Agrcl. Exp. Sta., 1910 



Fig. 437. — The squash-vine borer, Melittia satyriniformis 

 Hubn. a, adult male; b, adult female : c, eggs on stem: 

 d, full-grown larva in stem; e, pupa; f. cocoon. Enlarged 

 one and one third times. (After Chittenden. 1 T . S. Dept. 

 Agric. ) 



