380 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxv. 



on various plants at Sedalia. No moths were bred, but the larvre are 

 obviously the same as those formerly bred by me, and Xylcnn'ujea sim- 

 plex is native to the region, for I took it aljundantly at Manitou in 

 May, 1891. 



THYREION ROSEA Smith. 



Eggs. — Hemispherical, the base flat, about 28 vertical ribs, low, 

 rounded, diminishing regularly by alternation at the upper three- 

 fourths and ending at the micropyle, forming a slightl}' depressed ring; 

 vertex again a little elevated, reticulate. Cross-stria? faint, but the cell 

 areas slightly hollowed, a row on each side of each ridge, the joinings 

 in the hollows and on vertices of ridges which appear somewhat beaded; 

 color pearly white; diameter 0.8, height 0.4 mm. 



Stage I. — Head rounded bilobed, mouth pointed, shilling l)lack; 

 width 0.4 mm. Cervical shield black, excised at the posterior angles 

 and a little so on the dorsal line posteriorly; anal plate faintly dark 

 tinted. Body normal, white, no marks. Tubercles very small,, with 

 moderate, pointed seta?, black. Thoracic feet blackish ringed, abdomi- 

 nal ones normal, equal, pale. On hatching the larva? entered com- 

 pletely within the leaves of the food plant, where they burrowed 

 between the epidemics. 



Stage 11. — Head rounded, brown black; width O.G mm. Cervical 

 shield and plates dark l)rown; body all white, inunaculate, the small 

 tubercles dark. 



Stage III. — Head pale ^^ellowish luteous, sutures, area about eyes 

 and jaws broadly brown; width 0,9 mm. Body all whitish, cervical 

 shield a little shining and a shade yellower, but practically concolorous. 

 Tubercles minute, seta? moderate, dark. Feet normal; spiracles ])lack 

 ringed, rather round. 



Stage IV. — Head round, bilobed, compact, and smooth, vertex level, 

 clypeus rather high, nearl}' reaching the membranous triangle, showing- 

 dark brown; sutures and rims of lobes posteriorly blackish; width 1.2 

 mm. Cervical shield large, the posterior angles rounded, scarcely 

 notched behind, shining light brown, with two detached setfe on the 

 lower side not on a shield. Anal plate shining brown, with dark 

 tubercles. Body all opaquely white, the tubercles small, brown, with 

 short, stifi', dark seta?. Spiracles brown rimmed. Feet normal, the 

 crochets in a neat half circle on the inner side of the planta. Tul)ercle 

 iv at lower corner of spiracle. 



Stages V and VI were not obtained. The larva? feed at first inter- 

 nall}^ in the leaves of the wild onion, Allhwi sp. ; Mr, Oslar tells me 

 that he has seen them devour the whole plant, eating down into the 

 bulb. The moth flies at the time the plants are in blossom and rests 

 on the flowers, where it is inconspicuous, its pink and whitish colors 

 harmonizing with those of the blossoms. Found on the prairie near 

 Denver, May 29. 



