riERraAE: EURYMUS PHILODICE. 



1125 



According to Dr. Minot, these butterflies "pass the uiglit among tlie roots 

 of grass. Toward sunset they become less active and take shorter flights 

 when disturbed ; as it grows darker and colder they settle down deeper 

 among the roots and dried grass until it is almost impossible to find them. 

 When evening has coine tliey seem torpid and will allow themselves to be 

 trodden upon or picked up in the fingers. The legs then hang or are folded 

 under tiie breast, tlie tarsi of each pair crossed." 



Enemies. According to Mrs. Treat, the caterjjillars of tliis butterfly 

 are "greedily sought for and large numbers taken to the nest" of For- 

 nica sanguinea. (Chapters on ants, (55.) The actual parasites of the in- 

 sect are many less than would be expected of so common an insect. 

 Fletcher reports the destruction of a larva in a single instance by a Tachi- 

 nid fly, while, among hymenopterous parasites, Pteromalus puparum has 

 been bred from it by Lyman, and a small Braconid by Miss Murtfeldt, 

 Mesochorus scitulus Cress., a secondary parasite. Mr. Fletcher also states 

 that toward the autumn of 1887 "large numbers of these caterpillars were 

 found dead in the fields, bearing a cluster of bright yellow cocoons of a 

 small, pai'asitic, ichneumon fly," which Ashmead named for him Megoris- 

 mus uubilipennis. 



Desiderata. Our knowledge of this insect is comparatively peiiect, 

 but its hiemal condition is still undetermined ; if the larva liibernates in the 

 ultimate or penultimate stage, the duration of the chrysalis in spring re- 

 quires investigation. Whether the insect is triple brooded in tiie extreme 

 north is also doubtful. Mr. Minot's suggestion that the butterfly afi^ects 

 flowers of its own color should be examined. Strange to say, the insect 

 has rarely been found pai'asitized, which may account for its great abun- 

 dance. 



LIST OF ILLUSTRATIONS.— EUB7MUS PHILODICE. 



Egg- 



PI. 65, fig. 25. Plain. 



68: 14. Micropyle. 



Caterpillar. 

 PI. 72, fig. 3. Caterpillar at birth. 



76: 10. Full grown caterpillar. 



79 : 46. Head, first stage. 



47. Head, third stage. 



48. Head, fifth stage. 



86: 13. Last abdominal segment, beneath. 

 42. Dermal appendages, first stage. 

 Chnjsali.i. 

 PI. 84, fig. 54. Dorsal view. 

 55. Side view. 

 87:4. Ventral view, in front. 



Imago. 

 PI. 7, fig. ('•. E. p. pallidice J , both surfaces. 



8. E. p. philodice, 9 , upper surface. 



9. Male, both surfaces. 

 13 : 6. Female, both surfaces. 



8. Male, both surfaces. 

 35 : 4, 5. Male .abdominal appendages. 

 40:11. Neuration. 

 46 : 37. Androconium. 

 56:2. Side view, with head and appen- 

 dages enlarged, and details of the structure 

 of the legs. 



61 : 9, 10. Neuration of lore wing, <? , 9 • 

 General. 

 PI. 25, fig. 7. Distribution in North America. 



