1344 THE BUTTERFLIES OF NEW ENGLAND. 



A Tacliina fly, with a hairy body, and soinewliat lari^er tliati a common house-fly, 

 wliicli it superflcially rosi-mblcs, attacks the catei-pillai-s wlieii partly grown, and 

 deposits 111)011 each several elongate, oval, white eggs; these hatch maggots, which 

 penetrate the sliin of their host and feed upon its body-contents, eventually killing the 

 worm. The tachluized caterpillar usually attempts to pupate, but strength fails and 

 it dies suspended iu its silken loop. The parasitic maggots eat their way out and drop 

 to the ground, in which they form oval puparia. They emerge as flies in twelve or 

 fifteen days, or, if the season is far advanced, remain in the ground during the two or 

 three months of winter, and issue with the return of warm weather in February. 

 From four to eight flies are bred from a single Orange Dog. [He also adds :] From 

 the chrysalis there sometimes issues, instead of the butterfly, a four-winged fly. 

 This parasite [Chalcis robusta] is a large and handsome member of a family, the 

 Chalcididae, composed for the most part of minute forms. It is 8.1 mm. (3-10 inch) 

 long; In color black, with golden-yellow legs. The posterior thighs are swollen and 

 adorned with an oblique band of black across the middle. The \ving.s are smoky. 

 The head and thorax are very coarsely punctured, and clothed with short, goldeu hairs. 

 The fly in quitting its host makes a large, round hole in the side of the chrysalis. All 

 the specimens obtained emerged in June or July from pupae of the second brood. 

 There can be no doubt that this parasite would in case of undue multiplication of the 

 Orange Dog become an efficient check upon its increase. At present, however, it is 

 somewhat rare (Ins. orange, 1.39). 



Pteromalus vanessae (89 : 3) lias also beeu bred from this insect by A. H. 

 Miindt iu Ohio and AV. H. Edwards iu AVest Virginia, together with 

 Heuiiteles huuieralis, which is a parasite of this enemy. Finally Dr. Neal, 

 writing from Florida in 1883, says, "The Mutilla (cow ant) tliis year has 

 nearly cleared my trees of the cre-sphontes ; it snips out a piece from the 

 abdominal ring, takes a sip of the fluid, and then tiie 'sugar-ants' finish 

 the work.'" 



Desiderata. Whetlicr the northern leap of this insect is a permanent 

 acquisition or not, or whether its northern boundary is an ever fluctuating 

 one, is an interesting question to determine. Whenever it appears in new 

 localities it should be noted, and when it disappears record is equally 

 worthy. Where and how is the change made from two to three and to 

 four broods in the season ? What is the meaning of the long continuation 

 of some chrysalids? Do they tend to combine butterflies of distinct 

 broods ? The habits and postures of the butterfly are insufliciently known 

 and the dipterous parasite undetermined. Has the butterfly any special 

 means of protection, through odor or any other thing? So large and strik- 

 ing a butterfly would seem to be more than ordinarily in need of it. 



LIST OF ILLUSTBATIONS.—HERACLIDEtS CBESPHONTES. 



General. Chrysalis. 



PI. 27, fig. 2. Distrilmtion in North America. VI 85, fig. 8. Colored. 

 89 : 3. Pteromalus vanessae, a parasite. 9, 10. Outlines. 



Efff/. Imago. 



PI. 66, fig. 3. Plain. PI. 14, fig. 12. Male, both surfaces. 



68:19. Micropyle. 35:21-23. Male abdominal appendages. 



Caterpillar. 41 : 4. Neuratiou. 



PI. 73, fig. 1. Caterpillar at hirth. 57:3. Side view, with head and ap pen 



76 : 1'i. Mature caterpillar. dages enlarged, and details of the structure 



79:62-66. Front view of head, stages i-v. of the legs. 



