56 
MEMOIES OF THE NATIONAL ACADEMY OF SCIENCES. 
The conclusion seems to be with our present knowledge that the Lepidoptera, Tricboptera^ 
and Diptera may possibly have had a common ancestry, and that it may be found that the- 
Lepidoptera was the first to be differentiated, and the Diptera the last, since they are more highly^ 
modified. The line of descent of the metabolous orders might tentatively be thus exjoressed: 
H/menoptera 
Platyptera-like- forms 
VIII.— ATTEMPT AT A NEW CLASSIFICATION OF THE LEPIDOPTERA. 
The first step toward a scientific classification of the Lepidoptera was taken by Dr. Chapmau 
in his suggestive pajier on neglected points in the pupm of Heterocerous Lepidoptera. His 
division of the groups based on pupal characters is the following: 
LEPIDOPTERA-HETEROCEUA. 
A. OBTECTyE. Pupa smootli and rounded, externally solid, inner dissepiments flimsy. Free segments in both 
sexes fifth and sixth (abdominal). Never emerges from cocoon, or progresses in any way. 
Dehiscence hy irregular fracture. 
1. Macros, Larva with hooks of ventral prolegs on inner side only. (Exposed feeders.) Splilngesj. 
BomhyceSf Nolidiv, Kycteolidw, Noeiuina, Geometrw, 
2. Fyraloids. Larva with complete circle of liooks to ventral prolegs. (Concealed feeders.) PyraJeSf. 
Phyokltv, Eudorido’, Crambidie, Gelechidiv, Plutellida^j (Ecojyhoridw, (E})igraphiid<Vj AlucUidw.) 
3. L Doubtful whether Pyraloids or of separate (classificatory) value. Hyponymeutidce, Argyresiliidw, 
Coleophoridw. (Pcrittia?), (Elachistidjcf). 
B. IxcoMPLET.E. Pupa less solid and rounded, appendages often partially free. Free segments may extend 
upward to third (abdominal). Seventh always free in male, fixed in female. Dehiscence 
accompanied by freeing of segments and appendages previously fixed. (Except in 1) pupa, 
lirogresses and emerges from cocoon. 
1. Pupa attached by cremaster. Free segments. 4 5 6 7. 45 6. Pierophorma, 
2, Pupa free to move and emerge from cocoon. 
a. Larva concealed feeder, often a miner, and usually ratber active when not cramped by the mine. 
1. Free segments. 5 6. 5 6 7. JAthocolleiidw, Gracilariidcv, 
2. Free segments. 4 5 6. 4 5 6 7. 
rt. Tixe/E {Thieido’j Psychidw, Sesiidic), 
« h. Tohtrices (Toriricinat Co88H8j ExapaiCf Simaethis), (Castnia.) 
3. Free segments. 3 4 5 6. 34567. 
a, Zeuzera and Hepialus tend to lose third as a free segment (are gaining it as a fixed segment). 
1>. Tischekia, 
c. Adelid.e. Ovipositor (of imago) formed for piercing plant tissues. 
d. Nepticulid.e. Antenme separate from head in dehiscence. 
1). Larva exposed feeder. Slug-like iu form and movement, head very retractile. Free seguients,. 
3 4 5 6 7. 34 5 6. 
1. MiCROPTERYGtD.E.* Eight pairs abdominal legs, curious appendages, moss feeders. 
2. CociiLiOPOPiu.E. Legs evanescent, but traces of extra pairs and of curious appendages. Max. palps- 
large pi/pa, not in imago. 
3. Zygaexid.e. Legs of Macro type. Max. palps evanescent in pupa. 
^ I have only seen a portion of a p.upa of these and of Psychids. I have had none of my own, and have not heent 
able to examine them freely. — T. A. C. 
