378 TERTIARY INSECTS OF NORTH AMERICA. 



Table of tJit- species of Xi/sins. 



Autenn;e distiuctly more thau half as long as the body. 



Head distinctly loader t.haa broad ; body relatively slender 1. A r . vinctus. 



Head distinctly broader thau loug; body relatively stout 3. N. recula. 



Autenmc nearly or quite half as loug as the body, but not more. 

 Autenme half as loug as the body. 



Thorax tapering considerably, the apex hardly mure thau half as long as the base; membrane 



distiuctly infumated 3. JV. tritiin. 



Thorax tapering but little, the apex fully two-thirds as long as the base; membrane appar- 

 ently clear 4. N. ttrra;. 



AuteiiniB distiuctly less than half as long as the body 5. N. stratus. 



1. NYSIUS VINCTUS. 



Body slender, three times as long as broad ; head and thorax black, 

 the abdomen blackish fuscous, antennae and legs very dark testaceous. 

 Head considerably longer than broad, well rounded, heavily punctate. 

 Antennae distinctly more than half as long as the body, the basal joint stout, 

 the remainder slender, decreasing regularly and slightly in size from the 

 second to the fourth. Thorax rapidly tapering forward, the apical about 

 half the length of the basal margin, both truncate ; surface heavily punctate. 

 Apex of corium reaching scarcely beyond the middle of the abdomen, 

 corium infuscated ; membrane clear with distinct fuscous veins. 



Length of body, (i mm ; antennae, 3.6 mm ; breadth of thorax, 2 mm . 



Florissant. One specimen, No. 7310. 



2. NYSIUS VECULA. 



PI. 2'J, Fig. 7. 



Body as compared with the preceding species relatively stout, being 

 somewhat less than three times as long as broad ; whole body with the legs 

 blackish fuscous, antennae slightly paler. Head broader than long, rounded 

 subtriangular, smooth or scarcely punctate. Antenna 1 distinctly more than 

 half as long as the body, the basal joint moderately stout, projecting con- 

 siderably beyond the front, the remaining joints slender, the apical barely 

 incrassated and as long as the penultimate. Thorax tapering regularly and 

 considerably, the apical considerably more than half as long as the basal 

 margin, both truncate, the oblique sides without ampliation ; the surface 

 rather delicately punctate. Hemelytra with corium infuscated, reaching 

 somewhat beyond the middle of the abdomen ; all the veins delicately 

 punctate. 



Length of body, 5.5-5.G mm ; antenna*,, 3.75 mm ; breadth of body, 2.G mm . 



