REVISION MALACOSOMA HUBNER IN NORTH AMERICA 155 



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

 Alrius oregona, Alnus sp., Amelanchier sp., Piirshia tridentata, Rosa spp., 

 Salix spp., Prunus virginiana, Ribes sp., Ceanothus cuneatus, Betula glandu- 

 losa, apple, plum, cherry, and Populus tremuloides. 



TYPE. — Lectotype, here designated, a male in the United States 

 National Museum. USNM Type No. 34888. Size: 27 mm. wing- 

 spread, the wings somewhat drooping. Data: type; pluvialis Dyar; 

 7814; male genitalia on slide, Dec. 10, 1938, J.F.G.C. No. 2245. The 

 number "7814" = 7806 which is Dyar's catalog number referring to 

 "BB356" which are his field notes on this collection in his brown note- 

 book. These notes are mostly larval descriptions, but some of them are 

 interesting because he apparently was undecided at first whether to 

 describe this as a new species or regard it as Clisiocampa fragilis Stretch. 



TYPE LOCALITY. — The original description says it was found 

 abundantly at Seattle, Washington, and rarely at Portland, Oregon. 

 Dyar's notes indicate it was very common on alder at Lake Union, 

 Seattle, Washington, so his reared specimens most likely came from 

 there. Therefore, the t}^pe locality is restricted to the area around Lake 

 Union, Seattle, Washington. 



PARALEGTOTYPES.— Two adult males, one inflated and four 

 preserved larvae in the USNM. The inflated larva is mostly orange and 

 black with a small amount of blue laterally, and is a typical c. pluviale 

 larva. It would have been selected as the lectotype since this subspecies 

 is most clearly recognizable as a larva, except for the ^^ pluvialis Dyar" 

 label in Dyar's handwriting on the adult male. 



DISTRIBUTION (fig. 2).— As herein restricted, c.pliwiale's distribu- 

 tion follows fairly well the areas of higher rainfall west of the Cascades 

 in Oregon and W^ashington. It may extend southward in the fog belt 

 along the northern California coast, but only two early instar collections 

 were made along the coast (Nos. 68 and 69) and they were not success- 

 fully reared beyond the third instar, so they are regarded as M. cali- 

 jornicum. The Oregon-California border is set arbitrarily as the southern 

 boundary for c. pluviale until information demonstrating that it occurs 

 farther south along the coast is obtained. 



The southern boundary of the distribution from Washington to 

 Montana is next to impossible to define since this is an area of very 

 gradual transition from predominantly orange and black larvae in the 

 north to larvae farther south having progressively more blue in the 

 color pattern. Therefore, a more or less arbitrary boundary has been 

 selected which restricts the subspecies c. pluviale to northern and western 

 Washington, and treats those populations found in the Palouse area as 

 M. californicum. In Montana the Continental Divide is a good I'ough 



279-280 — 68 11 



