32 PROCEEDINGS OF THE ACADEMY OP 



form the Protamceba of Haeckle, from which has been reached 

 through endless ramifications the present regime. 



That our myriad forms of Butterflies have arisen from a single 

 form in a uniform direction, is an hypothesis that cannot be enter- 

 tained, in view of the array of evidence to the contrary. They 

 have certainly reached their present status by several roads ; but 

 assumed in their entirety, there can be no question about their 

 evolution from the Bombycidse. 



The Sphinges have been possibly reached from aTrichopterous 

 form through the Noctuidse and Bombycidee. Although this 

 family does appear to hold an intermediate position to Diurnals 

 and Nocturnals, and would seem to form a principal link in the 

 chain which has led to the former ; still the absence of any positive 

 testimony upon this subject effectually precludes an3 r such ar- 

 rangement. Were this the road bj T which the higher types have 

 been reached through the play of natural forces, we should expect 

 to meet some of the old landmarks, or to see in existing forms 

 some proofs thereof. 



The JEgeridse must also be traced back to a pre-existent Cad- 

 dice-fly. In their general form, in the outline and the transpa- 

 rency of their alar appendages, in their manner of flight, and the 

 time of the day when they are most active, the JEgeridae approxi- 

 mate the Bymenoptera. The genus Trochilium, of this family, re- 

 sembles in all the above particulars many of our ordinary Mem- 

 branous-winged insects. While this family undoubtedly leads for- 

 ward to the Hymenoptera, it reaches backward and claims a near 

 alliance with the Zygsenidse. 



These facts have strongly impressed my mind as to their near 

 relationship ; and the thought has been frequently suggested, may 

 not the Hymenoptera, the highest of insect life, have been reached 

 through some member of the JEgeridse. As Trochilium bears the 

 nearest approach to a Hymenopteron of any form of Lepidoptera 

 with which I am familiar, so the genus Cosmosoma of the Zygse- 

 nidse in many particulars'resembles Trochilium. From the Zygse- 

 nidse to Phryganea through the Noctuidse, retrocession is mode- 

 rately gradual. 



An examination into the provisions which lepidopterous larvae 

 make preparatory to entrance upon the chrysalis state, rather 

 countenances than opposes this theory. From the cocoon of the 

 least developed of our moths to the loop and girdle of the Papili- 



