1080 WALTER H. WELLHOUSE 



Cosmopterygidae 



curvilineella Chamb., Blastodacna (Hawthorn fruit miner) 



The larvae of Blastodacna curvilineella are very commonly found 

 tunneling in the fruit of native hawthorns in late summer. They become 

 full-grown in September and October, when they leave the fruit and 

 burrow into the ends of dead twigs or other decaying wood to hibernate. 

 The hibernation cavity is lined with silk, and in the early spring pupation 

 takes place there. The moths emerge in May and June. They are gray, 

 with two or three indistinct dusky longitudinal short streaks on the 

 wings, and have a wing expanse of 1 centimeter. 



The larva is from 9 to 10 millimeters long. In color it is yellowish 

 white, with a brown head and thoracic legs, red spots near the spiracles, 

 more or less blackish among the setae on the dorsum of each segment but 

 especially noticeable on the prothorax and the anal segment, and many 



patches of black setae arranged as 

 shown in figure 113. It feeds on the 

 pulp of the fruit and leaves many 

 brown pellets of excrement in the bur- 

 ,, row behind it. Often one whole side 



FlG. 113. LARVA OF BLASTODACNA f ., , I i 



CURVILINEELLA of a fruit ls mined out > leaving only 



the skin to cover it. 



The moths have been bred from larvae in Crataegus pruinosa, C. neo- 

 fluvialis, and C. macracantha, and the larvae have been found in a number 

 of other native hawthorns. The moth has been reported by Chambers 

 from Kentucky (1872) and from Canada (1875), and therefore it probably 

 occurs throughout the Eastern States. 



A closely related European species, B. heller ella Dup., feeds in the fruit 

 of hawthorns and also bores into young apple shoots (page 1116).' 



DlPTERA 

 Cecidomyiidae (Itonididae) 



absobrina Felt, Rhizomyia 



crataegifolia Felt, Lestodiplosis (Hawthorn f ringed-cup gall) 



Adults of both Rhizomyia absobrina and Lestodiplosis crataegifolia 

 have been reared by Dr. Felt from larvae in the galls. The galls are 

 green and cup-shaped, and are covered externally with round-tipped spines 

 4 or 5 millimeters in diameter and about the same in height (figs. 114 and 

 115). They .occur on the larger veins and petioles of leaves and on the 

 ends of young twigs of Crataegus pruinosa and C. macracantha. Several 

 galls are commonly found in a group on the same or adjoining leaves. 

 Those on the leaves are on the upper side, but extend through the leaves 

 to form a smooth, semi-globular swelling on the lower side. 



