138 ILLINOIS BIOLOGICAL MONOGRAPHS [138 



genus was placed in the table on the authority of Scudder's detailed 

 description of C. eubule. 



Synchloe (=Anthocharis) has several and various forms of larvae. 

 In >S'. genutia some of the prothoracic chalazae are very large and those 

 of the head are well developed, while in 8. sara and S. olympia the setae 

 of the head and prothorax are all small and borne on small chalazae. 



The larva of Phoebis argante var. maxima Neum. is large with a 

 small retractile head. 



The bright green larva of Eurymus philodice is well known in the 

 eastern half of the United States. It has a pair of distinct lateral lines 

 and a black spot below the line on each segment. E. eurytheme which 

 ranges eastward to some extent from its home in the Rocky Mountains 

 has a similar larval stage except that the black spots are either indistinct 

 or connected from one segment to another, 



Eurema nicippe has the setae all about the same size. The larger 

 chalazae of the head are larger than the ocelli. The larva of E. euterpe 

 (=lisa) is less than three-fourths of an inch long and the chalazae of the 

 head are all small. 



Family Papilionidae 



Larvae of the Swallow-tail butterflies are, like the adults, beauti- 

 fully decorated and outlined. No unpleasant spines or horns are present 

 to discourage the observer and no discordant colors to offend him. The 

 structure of all the species is so constant that it is necessary to have 

 recourse to color in their separation, but all of the characters used are 

 fixed and are seldom affected by alcoholic or other means of preservation. 



Head smaller than prothorax, somewhat retractile, shorter in dor- 

 sal than in ventral portion ; front not extending half way to top of head ; 

 labrum notched to about half its depth and bearing about thirty setae ; 

 ocelli six, subequal in size, fifth much closer to fourth than to sixth; 

 secondary setae short. Body cylindrical, usually tapering rather ab- 

 ruptly toward the head and gradually toward the caudal end, usually 

 widest in the region of the first abdominal segment; setae reduced or 

 absent on body but numerous on prolegs; intersegmental incisions in- 

 conspicuous; prolegs short, bearing a mesoseries of triordinal crochets, 

 sometimes with a lateral row, forming a pseudocircle ; lateral crochets, 

 when present, smaller than mesal, and biordinal. Osmaterium always 

 present; when retracted its location is shown by a long transverse 

 groove on the dorsum of the prothorax. In alcoholic specimens inserting 

 the points of a small pair of forceps assures the observer of the nature 

 of this groove and does no damage. 



Scudder divides the family into six genera, each including but one 

 or two species found in New England. Dyar's List discards three of 



