754 BOSTON JOURNAL 



Lengtli over three-tenths of an inch. 



-t Lines of the thorax only visible at base and tip. 



Length over one-fifth of an inch. 



LYROPS Illig. 



f Stemmata, one. 



1. L. ARGENTATA Beauv. — Black; tergum, segments mar- 

 uiaed with dark glaucous ; metathorax with a few wrinkles on 

 the posterior lateral margin. 



Inhabits the United States. 



9 Body black : collar having a gradually elevated angle on 

 the middle : wings slightly dusky ; a darker band at tip ; by an 

 obliquely transmitted light, opalescent, varying to purplish, and 

 at tip, in the darker portion, tinged with green ; recurrent ner- 

 vures entering the second cubital cellule very near to each other, 

 but little more than their own width apart : metathorax, poste- 

 rior lateral edge wrinkled transversely : tergum, posterior mar- 

 o'ins of the [371] segments dark glaucous, without any bright sil- 

 very reflection : posterior pair of tibiae at tip behind, with a fer- 

 ruginous spot. 'S More slender, wrinkles of the metathorax less 

 obvious, and the recurrent nervures at their entrance into the 

 second cubital cellule not quite so close together. 



Length 9 nearly half an inch. 



The color of the wings, by a particular, obliquely transmitted 

 light, is very beautifully perlaceous and somewhat iridescent. 



2. L. PEPTiCA. — Black ; tergum fasciate with glaucous, re- 

 flecting silvery. 



Inhabits Indiana. 



9 Body black ; reflecting silvery, particularly on the head and 

 feet : palpi piceous-yellowish : collar silvery on the posterior mar- 

 gin J thorax and scutel having their sutures reflecting silvery : 

 wings hyaline ; nervures honey-yellow ; recurrent nervures mod- 

 erately near each other at their junction with the second cubital 

 cellule : tergum, segments excepting the ultimate one, on their 

 posterior margins glaucous reflecting silvery : anal segment with 

 a bright golden reflection : feet black, reflecting silvery ; last 

 tarsal joint rufous. 



Length over half an inch. 



[Vol. I. 



