1360 THE BUTTP:RFLIES of new ENGLAND. 



to one of the side veins, but sometimes are found on the surfaee of the leaf 

 itself. The late Dr. Asa Fitch in his manuseri|)ts says tiiat July 27, 1858, 

 he "noticed a female at mid-day hovering around some caraway, oviposit- 

 ing. She gently settles on the end of a leaf, holding thereto with her feet 

 for a few moments, whilst she curves her abdomen forward and places an 

 egg upon the up])er surface of one of the small leaflets, and then gently 

 flies away to another leaf." Professor Hamlin once obtained six or eight 

 eggs fi"om a female after she had been impaled on a pin. The eggs hatch 

 in from five to nine, generally from seven to nine days with us ; in Cuba 

 Dr. (xundlacli has had tliem hatch in four days in midsummer. 



Food plants. This caterpillar will probably cat any of our native, 

 introduced or cultivated Umbelliferae, since it has been found upon a large 

 number of them, among which may be specified : carrot (Daucus carota 

 Linn.), marsh pennywort (Hj'drocotyle), poison hemlock (Conium macu- 

 latum Linn.), water hemlock (Cicuta maculata Linn.), also C. virosa 

 Linn, and C. bulbifera Linn., water parsley (Sium cicutaefolium Gmel.), 

 Apium divaricatum, celeiy (Apium graveolens Linn.), mock bishop weed 

 (Discopleura capillacea DeC), parsle}- (Carum petroselinum), caraway 

 ( Caruni carui Linn.), dill (Ancthum graveolens), fennel (Foeniculum 

 vulgare), Archangelica. false water drop-wort (Tiedemannia) and parsnip 

 (Pastinaca sativa Linn.). Dr. Chapman writes that in Florida the first 

 brood feeds on Apium divaricatum because there is at that season no other 

 umbelliferous plant for it to eat ; at the appearance of the second brood 

 Apium has disappeared and it must find some other ; tiiis he believes to be 

 Discopleura, but he once saw a female laying eggs on Hydrocotyle, and 

 Mrs. Treat has taken it on H. umbelhita Linn. In Septemiier or October 

 he met the full grown caterpillars on Tiedemannia teretifolia. Cicuta 

 maculata, he adds, is abundant in the marshes, but he has ne^'cr found the 

 caterpillars upon it. According to Gollmer, the caterpillar (if it l)e really 

 this species) feeds in Venezuela on Arracia esculenta. No one seems to 

 have found the larva on an^■thing but an umbelliferous plant, excepting Air. 

 Fletcher, who tells me that he has taken it on Dictamnus fraxinella, an 

 introduced plant of the rue family. 



Habits of the caterpillar. These caterpillars eat voraciously, espe- 

 cially iluring their last stage ; yet even in the preceding stage Professor 

 Hamlin observed one which doubled its length in a single morning, grow- 

 ing from half an inch to an inch in length and attaining a bulk ten times 

 greater. They feed in plain view, and when wishing to moult, especially 

 in the later stages, seem to mount to the outer surface of the plant to gain the 

 fullest exposure, perhaps to avoid the danger of being rubbed at that time 

 by the neighboring leaves moved by the wind, for they sometimes select 

 the stems where they rest head upward. I have noticed the same habit in 

 the European P. machaon, and both leave the cast-off skins untouched ; 

 changes of skin generally occur in the morning before ten o'clock. 



