THE ANCESTRY OF BUTTERFLIES. 235 



throughout with hooks, which, with the rigidity of the abdomen, allow it 

 to hang in an oblique position. 



Although closely allied to the European Potamis (Apatura Auct.), 

 Chlorippe is clearly distinct in every point of comparable structure. The 

 imago has slenderer antennae with a shorter and more abrupt club, slenderer 

 and briefer palpi, and there are many other differences in the legs and the 

 form and neuration of the wings. The mature caterpillar is remarkable 

 for its frill of spines at the back of the head, the far briefer but much more 

 bristling coronal tubercle and the stouter frontal triangle, as well as in the 

 division of the body segments into four and not five subsegments, the 

 coarser papillae and their occasional definite arrangement. The chrysalids 

 also differ in their prominent mesonotum, straighter ventral surface and the 

 shorter ocellar tubercles. 



Only one species is found in or near New England, Mr. Edwards after- 

 wards correcting his statement that C. celtis occurred there. The food- 

 plant of both, the hackberry, is, however, found on the banks of the 

 Connecticut at least as far north as Springfield, though rarely. 



EXCURSUS VIL—THE ANCESTRY OF BUTTERFLIES ; 

 THE PRIMAEVAL FORM. 



... all you restless tbiugs, 

 That dauce aud touruey iu the fields of air : 

 You, Psyche's postman, trim and debonair, 

 "With eye-like freckles on your bronzed wings ; 



Your secret 's out ! I know you for the souls 

 Of all light loves that ever caused heartache, 

 Still dancing suit as some new beautv toles ! 

 Nor can you e'er your flitting ways forsake, 

 Till the just winds strip off your painted stoles, 

 Aud sere leaves follow in your downward wake. 



Edith M. Thomas. 



In the history of human life nothing is more apparent than that indi- 

 viduals are born and perish, while families survive ; families die out, while 

 nations continue to exist ; nations also have their limits, and mankind 

 outlives them. 



It is the same in the past history of life in general, revealed to us 

 in the stony book of nature. Species come and go, while genera still 

 maintain their ground ; and, in their various times, genera, families, and 

 orders of animals appear and disappear, while the groups liigher than they 

 outlive them. From this it follows that the existing members of any 

 group are but the merest fragment of its true whole ; and yet it is in 

 large measure from this fragment that we must deduce the true character 

 and relations of the group, as well as its past history. Nowhere is this 



