REVISION MALACOSOMA HUBNER EST NORTH AMERICA 167 



COCOONS. — Cocoons are more compactly spun than those of 

 many other populations, almost always with little or no outer envelope 

 of silk, and are dusted with a whitish powder (fig. 310). 



FOOD PLANTS. — Egg m.asses were found on the following hosts: 

 Prunus fasciculata, Prunus andersonii, Purshia tridentata, Purshia glandulosa, 

 Ribes sp., peach and apricot. 



TYPE. — Lectotype, here designated, a male in the American 

 Museum of Natural History. Size: 26 mm. wingspread. Data: 

 Nevada; 2492; Clisiocampa fragilis Stretch; No. 8791, Collection Hy. 

 Edwards; M. fragilis Stretch, Lectotype, male, J. McD., 1942; Slide 

 No. Mai 1 ; Lectotype, Malacosoma fragile (Stretch), male, F. W. 

 Stehr 1963. Genitalia mounted on slide labeled: Lab. No. Mai 1, 

 Malacosoma fragilis Stretch, Loc. Virginia City, Nevada, Div. Ent. 

 Ottawa, male lectotype, J, McD. Dec. '42. 



Dr. McDunnough selected this specimen as the lectotype in 1942, 

 but never published it, so it has been redesignated here. This specimen 

 is browner than typical c. fragile collected in the Mojave Desert, 

 lacks the white scales along the veins, and the lines on the forewings 

 are conspicuously indented at only one point where they meet. See the 

 discussion of Stretch's Malacosoma types in Appendix II (page 283). 



TYPE LOCALITY. — Virginia City, Nevada. Specimens were 

 collected there in July according to entry "2492" in Henry Edwards' 

 personal catalog of his collection in the American Museum of Natural 

 Histoiy. Virginia City is at the extreme northwestern edge of what can 

 be considered the range of c. fragile. It is unfortunate that this is the 

 case, since both larvae and reared adults which were collected 2 miles 

 north of Virginia City during this study (Coll. No. 135) show a great 

 range of variation in color and pattern that clearly indicates this area 

 is a zone of intergradation between M. californicum recenseo to the west 

 and the central populations of M. californicum to the north and east. 

 The name 'fragile,'' however, has priority over "Clisiocampa mus Neu- 

 moegen," which was described from southwestern Utah in 1893, so 

 fragile is retained, even though most specimens from southwestern 

 Utah which feed on Prunus fasciculata are more typically like central 

 Mojave Desert c. fragile than are most specimens from the Virginia 

 City area. It must be remembered that specimens collected near 

 Virginia City may vary greatly, and often will not look like specimens 

 of c. fragile collected farther south. 



PAP^LECTOTYPES.— One male, four females, one cocoon, all 

 in the AMNH and bearing the Henry Edwards' personal catalog 

 No. "2492." 



