74 BULI.ETIN 132, UNITED STATES NATIONAl MUSEUM 



Male genitalia with outer surface of liarpe unspined: ciiciilliis 

 large, spoon-shaped, finely and evenly spined; neck incurvation 

 slight; neck and sacculus evenly and finely clothed with hair-like 

 spines. Uncas absent. Socii absent. Gnathos a weakly chitinized 

 band. Aedoeagiis long, slender, slightly curved and scarcely taper- 

 ing; cornuti a small cluster of moderately long, slender, deciduous 

 spines. 



Abdomen of male simple. 



Female genitalia with two thorn-like signa. Ductus bursae 

 rather long, unchitinized except at genital opening. Bursa coupla- 

 trix large, finely granulate at neck. 



A small North American genus closely related to Gymnandrosoma 

 and with affinities to the Endothenia group of the Olethrentinae. 

 The genitalia are typically Laspeyresiin ; but otherwise the genus 

 would go better with Endothenia than with Laspeyresia. Prob- 

 ably a primitive form and (with Gymnandrosoma) linking the 

 I-aspeyresiinae and Olethrentinae. 



KEV TO THE SPECIES OF ECDYTOLOPHA 



1. Fore wing with subapical bar distinct (1) insiticiana 



Fore wing with subapical bar nearly obsolete (very faintly indicated) — 2. 



2. Fore wing with subtornal spot on dorsum, distinct (2) mana. 



Fore wing with subtornal spot obsolete or very faint (3) islandana. 



1. ECDYTOLOPHA INSITICIANA Zeller 



(Figs. 10, 115, 340) 



Ecdytolopha msitieiana Zeller, Verb. Zool.-bot. Ges. Wien., vol. 25, 1875, 

 p. 266.— Packard, Fifth Report IT. S. Ent. Com., 1890. p. 359.— Fer- 

 NALD, in Dyar List N. Amer. Lepid., no. 5287, 1903. — Barnes and Mc- 

 DuNNouoH, Check List Lepid. Bor. Amer., no. 72.53, 1917. — Forbes, 

 Memoir 68, Cornell Univ. Agr. Exp. Sta., 1924, p. 397. 



An insect of considerable economic importance. The larva is a 

 stem borer in Robinia. It attacks only new groAvth and forms a 

 large elongate gall which cracks open with age and disfigures the 

 tree. In the vicinity of Washington there are two generations a 

 year; the species overwintering as larvae under the debris on the 

 surface of the ground in flattened bean-shaped cocoons made of 

 pieces of fallen leaves, evenly cut, sewed together, and lined with 

 silk. Pupation takes place in April, and moths from overwintering 

 cocoons issue from early May until the end of June. These lay eggs 

 which hatch in from 5 to 6 days; the larvae feeding up, pupating 

 and again producing moths from early July to early September. 

 The larvae feed up in about 20 days during summer ; but in the fall 

 take considerably longer, and those that hatch last from the eggs 

 often die before they have completed their growth. The entire life 



