REVISION MALACOSOMA HUBNER IN NORTH AMERICA 143 



Malacosoma ambisimilis (Dyar), Dyar, 1898, p. 6. — Dyar, 1903, p, 262. — Dyar, 

 1928, p. 623, pi. 86c.— Collier, 1936, p. 98.— McDunnough, 1938, p. 138. 

 Malacosoma calif ornica (Packard), sensu Essig, 1926, p. 697 (in part). 

 Malacosoma ambisimile (Dyar), Langston, 1957, p. 7-8. 



This subspecies is not distinguished by adult characters. Most adults 

 are identical with the adjoining subspecies M. californicum californicum, 

 and cannot be separated from them except by locality data (see page 

 140). 



ADULT MALES (figs. 182-184). — Male californicum ambisimile are 

 more uniformly colored than male californicum californicum which range 

 from dark reddish-brown to light yellowish. Male c. ambisimile are 

 usually various shades of reddish-brown (fig. 184) and have the wings 

 crossed with yellowish lines as do dark c. californicum, but very few of 

 the lighter, yellowish specimens have been seen from the distributional 

 range of c. ambisimile. Terminalia (figs. 20, 45, and 65) are as described 

 for the northwestern populations of M. californicum, with the prongs of 

 the accessory claspers usually closer together than in figure 20; more 

 like figure 19. See description of terminalia for northwestern popula- 

 tions of Af. californicum under "comments" (page 128). 



ADULT FEMALES (figs. 185-187).— Female c. ambisimile are also 

 similar to female c. californicum, ranging from light yellowish to medium 

 yellow-brown, with dark lines crossing the forewings which are bordered 

 by lighter areas in darker specimens. Genital plate unsclerotized or 

 only slightly so. Ovipositor lobes as in figure 97, usually with the dorsal 

 lobe reduced. See description of terminalia for northwestern popula- 

 tions of M. californicum under "comments" (page 128). 



MATURE LARVAE (figs. 354 and 355).— Head black, sometimes 

 lightly mottled with blue, covered with fine yellowish to whitish setae. 

 Middorsal area of body black, usually without a stripe, but occasionally 

 with a fine whitish line on some segments. Addorsal area black with 

 weak, longitudinal, irregular, wavy orange lines which are obscured in 

 many specimens. The orange lines are more distinct in early instars and 

 preserved specimens. Subdorsal area black, the posterior subdorsal 

 spot generally present as a distinct blue-white spot which is usually 

 conspicuous, but may be small or absent on some specimens, or ex- 

 tended ventrally to form a vertical dash; anterior subdorsal spot present 

 or absent; if present it may be smaller than posterior spot or about 

 same size, in which case it may be extended anteriorly and posteriorly 

 to form an oblong horizontal mark. Subdorsal line usually absent, but 

 occasionally visible as a broken yellow-orange to orange line. Supra- 

 spiracular and subspiracular areas generally conspicuously blue-white 

 to blue-gray, sometimes streaked with orange when bluish color is weak. 

 Ventral area usually mottled gray-white and black, and with a median 



