94 
Psyche 
[March 
(without diapause) elsewhere as well. So far as is known, eurydice 
is single-brooded everywhere. Larvae of both species turn from yellow 
green to straw yellow when in diapause, and are capable of changing 
color in either direction overnight. 
A usually small emergence of fresh eurydice occurs in some 
localities in New York, New Jersey and Pennsylvania in the first 
half of August, four to five weeks after the principal emergence. 
Males of this late “brood” are frequently of the dark form noted 
above. It is very unlikely that these butterflies are descendants of 
those which emerged a month earlier. There may be a genetic basis 
for the emergence times; a bimodal emergence of Hyalophorct cecropia 
(L.) (Saturniidae) was recently reported by Sternburg and Wald- 
bauer (1969), with no genetic data. We do not believe the late 
eurydice are identical with fumosa , but the slight possibility exists 
that they represent another sibling species, unrecognizable in the 
adult except by its flight period and a statistical color difference. 
We have not obtained ova from these insects. 
Food Plants. — Dos Passos (1969) speculates that a food plant 
difference between L. eurydice and L. appalachia is likely. How- 
ever, our observations suggest that both are sedge-feeders and that 
neither is species- or group-specific within Carex. Female appalachia 
occur near sedges in shrub swamp or forest habitats where observa- 
tion is difficult. One oviposition was seen in the field, on Carex 
lacustris Willd. (Cyperaceae) at Texas Hollow, Schuyler Co., 
N.Y. Other sedges commonly associated with this species in New 
York, all of which were completely acceptable in the laboratory, 
are Carex gracillima Schwein., C. lanuginosa Michx., and Scirpus 
georgianus Harp. Wild hosts of L. e. eurydice in central New 
York include C. lacustris , C. stricta Lam., C. rostrata Stokes, and 
C. trichocarpa Michx. All of these sedges were fully acceptable to 
both species, as are some dozen other species tested (mostly undeter- 
mined). We reared both species from egg to adult on Carex torta 
Boott. Neither species would accept any of the following grasses 
(Gramineae) : Festuca ovina L. ; Elymus riparius L. ; Brachyelytrurn 
erectum (Schreb.) Beauv. ; MuhleTibergia schreberi Gmel. ; Agrostis 
alba L. ; Phalaris arundinacea L. ; Leersia oryzoides (L.)Sw. ; Echi- 
nochloa crus-galli (L.) Beauv. ( B . erectum and P. arundinacea 
are wild food plants of Lethe portlandia anthedon A. H. Clark, 
and M. schreberi is acceptable in the laboratory; Shapiro and Carde, 
1970.) 
