NO. 16S7. THE TnORAX OF TXFiECTf^—fiX0DGRA88. 565 



Tliis double nature of the meso- and metacoxa3 is common to Neu- 

 roptera, Mecoptera, Trichoptera, and Lepidoptera, and it has often 

 ))oen adduced as evidence of the double nature of the eutii-e segment. 

 Since, however, it can be shown in all these orders to be a purely 

 secondary adult character, it is evident that it has no such significance 

 Avhatever. 



5. Wing base very sim]:)]e in the ])upa (1-11). Articular elements 

 and bases of the veins of typical sha])e in sulults ('200, 201). 



XI. TRK^TOPTERA. 



Species studied. — Ncuronia oceUtfera (140, 148), Plntyphylax siih- 

 fascldfa, P. desic/nata, larva^ and pupa^ of unknown species. 



Character isfics. — 1. Only one prei^arapterum (148/^) present, fused 

 with episternum. Pronator disc carried by upper edge of episternum. 



2. Trochantin {T71) of meso- and metathorax crowds episternum 

 {Ej^s) from coxal articulation. 



3. A wing of the meso- and metasternum {S) extends dorsally 

 before the trochantin {Tn) to the episternum (Eps). 



4. Meso- and metathorax similar to each other in size and structure. 



5. Meso- and metacoxa? {Cx) of adult wdth a j)osterior segment 

 {epm) as in Xeuroptera. This can be shown by a study of the. pupa 

 (140) to be a detached piece (epm) of the epimeruTn (Eptn), which 

 has extended downward behind the coxa and fused upon it. 



The Trichoptera stand in a position intermediate between the Neu- 

 roptera and the Lepidoptera. The resemblance of the Ti'ichopteran 

 pleurum to that of a generalized moth like Phassus (149) is very 

 striking. 



XII. I.EPIDOl'TEKA. 



Species studied. — Phassus argciitiferus (149, 150, 151, 152, wing 

 bases, 202, 203), P. triangularis (153, 154), Cossidae; Protoparce 

 cingidata (155-159, wing base, 204), Sphingida^; Pitheronia regaJis, 

 Citheroniida^. 



Chai^acteristics. — 1. Microthorax represented by one or two sclerites 

 on side of neck (152 ?«/, mi). 



2. Pronotum w^ell developed in lower families (152 N) \ reduced 

 and longitudinally compressed in higher families, often forming two 

 flat lateral lobes which even become constricted at the base into two 

 stalked plates, the patagia. The patagia are specially well developed 

 in Agrotis. A comparative study would show them to be simply 

 developments of the notinn, and there is no ground for regarding 

 them as homologues of the wings, nor even of the tegula\ 



3. Propleurum narroAV (152). Epimerum {Epm) specially re- 

 duced, generally obsolete. Episternum (Eps) prolonged upward as 

 a narrow prenotal band, overlapped by edge of notum. 



