THE CANADIAN ENTOMOLOGIST. 351 



DESCRIP'I'ION OF A NEW SPECIES OF SAW-FLY. 



BY WARREN T. CLARKE, AUBURN, ALABAMA. 



Doleriis Cookei, n. sp. — Female. — Eength, 4 to 4.5 mm. Expanse 

 of wings from tip to tip, 8 to 9 mm. General colour effect of body dark 

 brown to black. Head back of, about and beneath ocelli, black, sparsely 

 clothed with whitish hairs. Clypeus sinuate, incurved, yellow, sparsely 

 pilose. Labrum polished yellow. Antenna dark brown to black, stout, 

 pilose. Joints i and ii subequal, short; rest subequal, longer. Antennal 

 fovea? circular, deep. Thorax : tergum black, sparsely clothed with 

 whitish hairs ; pleura and venter polished black. Wings smoky brown ; 

 first submarginal cell irregular oblong ; veins dark brown to black. No 

 clear spot at base of wings. Legs yellow, shading to brown ; tibial spur 

 not bifid, yellow. Abdomen stout, black, sparsely pilose. Saw yellowish, 

 marked with dark brown, sheath black. 



Male. — Length, 3 to 3.5 mm. Expanse of wing:; from tip to tip, 7 to 

 7.5 mm. General colour effect of body yellow. Head back of, about and 

 beneath ocelli, polished yellow, sparsely cioihed with white hairs. 

 Clypeus sinuate, incurved, yellow, slightly pilose. Labrum polished 

 yellow. Antennas stout, yellow, joints i and ii subequal, short ; rest 

 subequal, longer. Antennal fovere circular, dee]). Thorax : tergum dark 

 brown, clothed with white hairs. Pleura and venter polished yellow. 

 Wings hyaline, veins yellow-brown. First submarginal cell irregular 

 oblong ; no clear spot at base of wing. Legs yellow ; tibial spur not 

 bifid, yellow. Abdomen medium slender. Tergum and pleura dark 

 brown, marked with yellow; venter yellow ; all slightly pilose. 



Habitat, California. 



The sexes are readily separable by the colour and size dimorphism 

 shown in the species. The insects are single-brooded, the eggs being 

 placed in the tissue of the calyx ring or sheath of the cherry and plum 

 blossom, just beneath the outer epidermis. Incubation is accomplished 

 in from five to seven days, the young larvi^ boring into the newly forming 

 fruit and devouring the embryo. The larv?e attain their full growth in 

 from 21 to 25 days, being then about seven millimeters in length. They 

 then pass down to and into the ground beneath the trees, there forming 

 small cells, in which pupation takes place later on. In the following 

 spring the adult insect appears, and the cycle is completed. 



This species can be distinguished from the other species of D )lerus 

 known in California by the following table : 



October, 1906. 



