BAGWORM MOTHS OF THE WESTERN HEMISPHERE 133 



abounded in late April, Vorhies found that larval growth had been 

 completed and the moths had emerged when he examined the same 

 infestation in early July. Thus, the larval period may last only a 

 few weeks, or it may be extended over several months. Vorhies has 

 observed both the hatching of eggs and the presence of larvae of various 

 ages as late as October 16 and as early as March 31, which indicates 

 winter survival of both eggs and larvae. The main period of adult 

 emergence is probably during June and July but var^dng dates have 

 been reported from March 31 to October 19. 



Material examined. — 20 cf cf , 2 9 9, 128 cases: 



Arizona: Specific locality unknown, 40 cases, USNM. Tucson, 2 cf cf , June 10, 

 July 9; cf, Sept. 12; 9, May 1; 9, Oct. 1; 65 cases, USNM. Phoenix, 5 cf cf, 

 June 14, ANS. 



California: Cabazon, 9 cases, USNM. Los Angeles, 5 cases, USNM. Mojave, 

 10 miles north of, 5 cf cf , June 28-July 25, USNM. Mojave Desert, 7 d'cf, 

 July 10-12, USNM. San Bernardino Mts., 2700 ft., cf with case, USNM. 

 Whitewater, Colorado Desert, 4 cases, CU. 



Texas: El Paso, 3 cases, USNM. Terlingua, 12 miles north of, case, USNM. 



54. Thyridopteryx alcora Barnes 



Figures 60, 115, 239, 293, 293a, 359; Map 5 



Thyridopteryx alcora Barnes, Can. Ent., vol. 37, p. 214, 1905. — Jones and 

 Parks, Tex. Agric. Exp. Sta. Bull. 382, p. 32, figs. 15, 20, 1928.— Dalla 

 Torre and Strand, Lep. Cat., pars 34, p. 184, 1929. — McDunnough, Check 

 List Lep. Canada and USA, pt. 2, no. 9521, 1939. 



Male. — (Fig. 60.) Very similar to T. ephemeraej'orm,is in general 

 appearance. Vesture of body fuscous to black. Antennae 36- to 

 40-seginented, segments longer than broad beyond basal fourth. 

 Middle, hindtibiae each with single, small apical spur. 



Apex of primaries not as extended as in T. ephemeraejorrnis, thus 

 outer margin less oblique, less curved; tornus more prominent than 

 in other species. Wings of flown specimens in general with somewhat 

 more abundant scaling than T. ephemcraefonnis ; membrane trans- 

 parent; majority of scales (fig. 359) of cell 2A in forewing relatively 

 broad with dentate apices, those at base of cell usually quadridentate, 

 gradually tridentate further out; M2+3 sometimes separating before 

 margin in both wings. Wing expanse 24-26 mm. 



Male genitalia. — (Fig. 293.) Very similar to T. ephemeraejormis 

 except vinculum tapering more abruptly to saccus. 



Female. — Unknown. 



Case. — (Fig. 115.) Length 30-40 mm.; diameter 7-9 mm. All 

 cases examined completely overlaid with small stems, twigs arranged 

 in oblique manner, thereby resembling stick cases of T. meadi. In 

 T. alcora sticks relatively longer, posterior ends frequently diverging 

 from bag, thus imparting to case a bulkier appearance. 



