34 



MISCELLANEOUS RESULTS OF WORK OF BUREAU IX. 





will be understood that the locality Hugo, Colo., is the one in which 

 he collected specimens for identification. This account does not pre- 

 tend to be an exhaustive one, but is more in the nature of a list, with 

 notes on such species as appear to be concerned in killing out the weed. 

 Considering the toxic qualities of the locos, the insects which affect 

 them, with some exceptions, ma} T be classified as highly beneficial, 

 since the species which have just been mentioned have in some cases 

 completely rid large areas of loco weeds. 



THE FALSE-INDIGO GALL-MOTH. 



i Walshia amorphella Clem.) 



Prior to 1886 the larva of this species was known omy as a gall 

 maker on the stems of false indigo (Amorpha fruticosa) and was 

 described from moths reared from that plant in 186-1. An account 



of the species and its 

 habits was afterwards 

 given by Riley in 1870. a 

 He stated that as the 

 twigs invariably with- 

 ered and died above the 

 gall, and as the shrub 

 was of no special value, 

 the species might be 

 placed among our harm- 

 less insects. In early 

 records of the Bureau 

 of Entomology there are 

 numerous references to 

 this species and its oc- 

 currence on false indigo. 

 In 1886 a second food plant. Astragalus mollissimus, was recorded. 6 

 This moth (fig. 8, a) belongs to the family Tineida? and has a wing 

 expanse of about half an inch. It is grayish yellow, spotted with 

 dark brown, and both wings are provided, as in others of this group, 

 with very long posterior fringes, longer than the wings themselves. 

 The larva or caterpillar (fig. 8, b) is yellowish white, with the head 

 and thoracic plate dark brown. It measures from a third to two- 

 fifths of an inch in length. 



Our records of the distribution of this species show that it has been 

 observed most commonly from Iowa and Missouri westward to Cali- 

 fornia, although it occurs also in the Atlantic region. It is quite 



a 2nd Kept. State Ent. Mo., pp. 132-133. 

 b Proc. Ent. Soe. AVash., Vol. I, p. 30. 



Fig. 8.— False-indigo gall-moth | Walshia amorphella) 



male moth; h, larva; c, gall in false indigo, showing exit 

 hole near top: '/. gall opened, showing larva in situ, a, b, 3 

 times natural size; d, c. natural size. I After Riley.) 



