INSECTS INJURIOUS TO THE LOCO WEEDS. 39 



larval staso it displays a remarkable diversity of habits, althouo:h it 

 IS evidently by choice a root feeder and is also, with the seed-corn 

 maggot and many related insects, a scavenger by nature, following in 

 some cases original attack by some other form of insect. It has been 

 recorded by Dr. L. (). Howard as having been bred from larva) in 

 human excrement in houses and out of doors. Mr. E. G. Titus has 

 reared it from sugar beet collected at Olney, Colo., and from cockle- 

 bur collected at St. Matthews, S. C, where it was feeding in the cells 

 of a weevil, Bar'is transversa. In September, 1905, it Avas reared by 

 the writer from (mions infested by Tritoxa flexa from Williamson 

 School, Pa., and there is positive evidence that it had fed on the 

 onion bulbs, as neither stems nor leaves were present. Dr. J. B. 

 Smith also has reared it from onions. In 1000 it was reared from 

 corn on the farm of Dr. B. T. Galloway near the District of Colum- 

 bia, where it was reported injurious, the injury^ being at first attrib- 



FiG. V2. — Spotted root fly {Bua-csta noUita) : Adult male at right; female at left. 

 Much enlarged (original). - 



uted to the .seed-corn maggot, as attack Avas to seed corn and resem- 

 bled the work of the latter species. From cabbage it has been reai'ed 

 on two occasions, viz, from the roots collected at "Washington, D. 

 C, and from maggot -infested roots received from Bethel, Alaska. 

 It has also been bred from the pulp of Osage orange, from apples in- 

 fested by the codling moth, from sumach fruit, from the bolls of 

 cotton, and from Solanum. It is not rare in diseased cotton bolls. 



This fly belongs to the same family as the preceding, the Ortali- 

 dre, and is shown in figure 12, where it will be seen that it has a large 

 head and flat body. Each wing is marked Avith two black spots. 

 The female is distinguished from the male b}'^ its more slender form, 

 smaller head, and pointed abdomen, Avhich bears near the anal ex- 

 tremity a distinct Avliite transverse band. The body is metallic blue. 



Our rearings shoAv that larva^ have come under observation from 

 May 27 to as late as October 2 and that flies have issued from various 

 sources June 10-July 30, September 8-21, and throughout October. 

 78936°— Bull. 64—11 4 



