4 Bulletin of the Brooklyn Entomological Society Vol. XVI 



Somite io: 



Tergum A divided sclerite interrupted dorsally by the opening 

 of the anus and crowded out of position by the enormous ter- 

 gum 9. Ventrally the two portions of this sclerite are united 

 to the small, square, tenth sternum. In the higher Lepidoptera, 

 tergum 10 is often produced above the anus into a dorsal hood 

 or hook, the Uncus of Pierce. 



Sternum: A small square or rectangular sclerite, ventrad to the 

 anus, simple in the genera Pielus and Gorgopis but in Hepialus 

 and Stenopis possessing a spatulate, median appendage, articu- 

 lated by an elbow joint and probably serving as an intromittent 

 organ for the penis which opens just behind it. Sternum 10 

 is plainly homologous with the Gnathos or Subscaphium of 

 Pierce as its position ventrad to the anus would indicate. 

 Whether its appendage, in Hepialus and Sthenopis is homolo- 

 gous with appendage III, the distal part of the ^Edoeagus, is 

 rather questionable and its occurence is too inconstant to sub- 

 stantiate any definite conclusion. Its function, however, is un- 

 doubtedly the same as that of the yEdoeagus of the higher 

 Le'pidoptera. 



Somite ii: Tergum and sternum 11 are not developed in this 

 family except in the genus Gorgopis having been supressed by 

 the invagination of the anus within tergum 9. In Gorgopis 

 tergum 11 is well developed forming a hood-like Scaphium 

 covering the anus dorsally and laterally. 



The Cerci which are regarded as appendages of somite il 

 (Appendage IV) are lacking. In the genera Gorgopis and 

 Pielus tergum 9 bears a pair of small chitinous processes 

 caudad to the first pair found in all the genera examined, and 

 dorsad to the anus, a position suggestive of Cerci, but their 

 structure and articulation would indicate that they are only a 

 secondary pair of processes. 



In the higher Lepidoptera there is a pair of appendages 

 laterad to the Uncus and attached to tergum 9. These are 

 called Socii and are probably homologous with the Cerci 

 although it is barely possible that they are structures developed 

 independently within the order Lepidoptera and in no way 



