1042 THE BUTTERFLIES OF NEW ENGLAND. 



The fossil remains of a butterfly belonging to this group, Collates 

 proserpina Scudd., has been found in the tertiarics of Aix, France ; and 

 another, long known as a Vanessa, under the name of pluto Heer, in the 

 miocene of Croatia. 



Table of genera of Bhodoceridi, based on the egg. 



Vertical ribs comparatively few (less than twenty) anj distant. 



Base much broader than summit, the egg not more than twice as high as broad. Callidryas. 



Base hardly broader than summit, the egg two and a half times higher than broad 



Eurymus. 

 Vertical ribs very[numerous (thirty or more) and approximated. 



Hardly more than three times higher than broad, considerably broader at base than at 



summit Eurema. 



Three and a half times higher than broad, not much broader at base than at summit. 



Xanthidia. 



Table of genera, based on the caterpillar at birth. 



Appendages of body as long as the segments that bear them Euruma. 



Appendages of body no longer than the section of the segments upon which they are seated. 



Eurymus. 

 Callidryas and Xanthidia unknown. 



Table of genera, based on the mature caterpillar. 



Hair bearing papillae both of body and head moderately conspicuous, distinctly elevated, 

 higher than broad; head relatively narrow. 

 Larger papillae arranged in a single transverse row on each subsegraent and much 



greater than the smaller ones ; first thoracic legs exceptionally short Callidryas. 



Larger papillae not detinitely ranged transversely, nor much larger than the smaller 

 papillae; first pair of legs shorter than the others but not to so great a degree as 

 in Callidryas. 

 Papillae of head comparatively large, very high and numerous, the largest of greater 



diameter th.an the Largest ocelli Xanthidia. 



Papillae of head comparatively small, moderately high and sparsely distributed, the 



largest smaller than the ocelli Eurema. 



Hair bearing papillae whether of head or body mere raised points, not distinctly higher than 

 broad ; head relatively broad Eurymus. 



Table of genera, based on the chrysalis. 



Ventral protuberance of wings doubling the depth of the body ; frontal process trebling or 

 more than trebling the length of the head above. 

 Anterior axis of body bent at an angle of 120° with the posterior axis; fourth abdominal 



segment with a distinct, sharp, supralateral carina Callidryas. 



Anterior and posterior axes of body in nearly a straight line ; suprastigmatal region of 

 fourth abdominal segment with no di.stinct carina, at most a broad swelling. Xanthidia. 

 Ventral protuberance of wings not doubling the depth of the body; frontal process only doub- 

 ling or less than doubling the length of head above. 

 Head above including frontal process twice as long as the prothorax, the process slender, 



acuminate; cremaster scarcely channelled above Eurema. 



Head above including frontal protuberance not more than half as long again as the protho- 

 rax, the protuberance slightly less than rectangular; cremaster deeply channelled above. 



Eurymus. 



