98 
Psyche 
[March 
species eurydice , appalachia and portlandia (in the broad sense, 
including anthedon ) divide neatly into “non-competing” pairs: the 
two sedge feeders ( eurydice and appalachia) differ in habitat; the 
two woodland species ( appalachia and portlandia) differ in larval 
food plant. (Similarly, in sexual behavior^ eurydice and appalachia 
are essentially non-territorial; portlandia is strongly territorial.) 
Lethe and the genera closely related to it are hypothesized to 
have originated in southeast Asia (Miller, 1968), a region with 
many forest-dwelling, grass- (mostly bamboo-) feeding representa- 
tives of both the eurydice and portlandia groups. It seems reason- 
able that the ancestors of both these groups migrated to North 
America via the Bering land bridge in the Arcto-Tertiary forest, 
and were forced southward by the events of the Pleistocene. 
With the vast majority of the many Asian Lethe feeding on 
grasses, the evolution of sedge feeding in North America by the 
ancestor of the eurydice group is a tempting hypothesis. Evolution 
of this trait by proto -eurydice independent of competition with 
proto -portlandia or by character displacement in sympatry with it are 
both possibilities. T. Shirbzu (pers. comm.) informs us that Lethe 
marginalis Motschulsky, which seems to be a member of the eurydice 
group, feeds on non-bamboo grasses and on sedges in Japan, as does 
Kirinia epaminondas Staudinger, formerly placed in Lethe. Ninguta 
{“Lethe”) schrenckii Menetries is an obligate sedge feeder. 
On the other hand, the speciation of eurydice and appalachia may 
have occurred when one of the Pleistocene glaciations isolated some 
populations of proto -eurydice in prairie to the west of populations 
in the eastern Austral forests. Virtually the entire range of eurydice 
was glaciated, and the distribution is therefore of recent origin. The 
same can be said for the northern portions of the ranges of appalachia 
and portlandia, but the southern portions are characteristic of many 
organisms which presumably survived the Wisconsin (and earlier 
glaciations) in the southeast. The lack of recorded relict populations 
of eurydice south of Pennsylvania in the Appalachians, if not due to 
inadequate collecting, suggests that the species did not have a Wis- 
consin refugium in the forested Austral Zone of the southeast; its 
habitat preference and developmental rate support this interpretation. 
(We do know of species of Hesperiidae, e.g. Euphyes bimacula , with 
ranges and biologies substantially similar to L. eurydice , which have 
relict populations in the southeast; Shapiro, 1970b.) Its most prob- 
able refugium, then, was in glacial Transition Zone somewhere west 
of the Appalachians. The existence of L. e. fumosa also supports 
