166 Psyche [August 
WESTERN LEPIDOPTERA. III. 
Notes oN LEPTARCTIA CALIFORNIAE WALKER. 
By Karu R. Coo.iner, 
Palo Alto, California. 
Some time ago while looking over the lepidopterological collection 
of Mr. J. G. Grundel, of Alma, Cal., I was struck by the great 
range of variation exhibited by Leptarctia california, a rather com- 
mon Arctian in the vicinity of San Francisco Bay. In one series 
of thirty-eight specimens, all from the same lot of eggs, hardly any 
two were at all alike, and no two exactly so, although californi@ is 
quite a plainly fashioned insect. The history of Leptarctia cali- 
fornie well illustrates the numerous troubles caused by a species 
much given to variation. The genus Leptarctia was established by 
Stretch, in his Zygenide and Bombycide of North America (p. 119), 
with lena Boisd. (—adnata Boisd.) and decia Boisd., both of which 
had been described in the genus Lithosia,’ and a new species, which 
he called dimidiata. These forms he tabulated as follows: 
Bonded Gypbovuiss 1iXelae Han o gue eb COUGodnDoonb op oDieSaqadoD5C L. decia 
bower svitigs yellowtwe: cen ee ote eer ees ies eee ae oie L. lena 
ower swans blacks. arin ci cisctelecheseienel-eyerotcre orto L. dimidiata 
These three species we find depicted on plate 5, nine figures of 
lena, three of decia, and four of dimidiata being given. Stretch 
was evidently aware of the great amount of variation displayed in 
Leptarctia, as he remarks on page 121, under L. lena, ‘““The wonder- 
ful variations of this species, show how necessary it is to have a long 
series of many insects before it is possible to determine the limits 
of the species. It is possible to select three or four types of the 
insect under consideration, so unlike each other, that in the absence 
of intermediate intergradations they might readily be considered 
specifically distinct; it was indeed a long time before I could satisfy 
myself of their identity, especially as the shape of the primaries is 
by no means constant, but the past summer has supplied so many 
intermediate links that there can be no longer any reasonable doubt.” 
In 1855, however, Walker had described in the British Museum 

1Five species of Cithene were also placed in the same genus by Boisduval. 
Subsequently he remarks that the three former (lena, adnata and decia) “should 
perhaps be placed in a new genus near Nemeophila.”’ 
