THE SHIELD-BACKED BUGS. 45 



slightly surpassing the cheeks ; beak reaching middle of second 

 ventral, its second joint almost as long as third and fourth 

 united; second antennal (in our eastern species) more slender 

 and nearly one-half longer than third, the latter subclavate; 

 fourth and fifth joints subequal, much stouter and more than 

 one-half longer than second. Pronotum subhexagonal, its 

 lateral angles obtusely rounded ; disk less declivent in front 

 than in preceding genera. Scutellum covering one-half or more 

 of costal border of elytra. Osteolar canal straight or feebly 

 curved, reaching nearly to tip of its supporting plate, its apex 

 obtuse. 



This genus was first characterized by Uhler (1871, 93) as 

 Aulacostethus, this name, as shown by Bergroth, being preoccu- 

 pied. One species is known from our territory and another 

 from Arizona and California. 19 



8 (11). Stethaulax marmoratus (Say), 1831, 2; I, 310. 



Dull reddish-brown, irregularly marked with fuscous, the latter form- 

 ing several narrow, transverse lines on pronotum and numerous similar 

 lines and blotches on scutellum ; disk of scutellum with many widely 

 scattered, small, slightly elevated smooth yellow spaces; connexivum with 

 alternating reddish-yellow and fuscous spots; under surface dull yellow, 

 the sides of pleura and abdomen with numerous fuscous or reddish-brown 

 punctures; antennae and legs yellow, the latter with fuscous or reddish- 

 purple dots. Head densely, shallowly and confluently punctate. Pronotum 

 less densely punctate, the punctures separated by at least their own di- 

 ameters and mostly arranged in sinuous transverse lines. Scutellum more 

 densely and deeply punctate, the intervals between the punctures mi- 

 nutely alutaceous; its disk with a faint median carina in front of de- 

 clivity. Sixth ventral of male broadly concave; genital plate semicircu- 

 lar, one-half wider than long. Length, 6 — 7 mm.; width, 4.5 — 5.5 mm. 



Lakehurst, N. J., May 7 — Sept. 16 (Barber and Davis). While 

 the known range of this species extends from New York and 

 Maryland to Georgia and Texas, it has not been taken in 



^'This is what I take to be the Aulacostethus simulans of Uhler (1876, 272) 

 described from near San Francisco. Van Duzee (1904, 76), after an examination of 

 a single female in the Henshaw collection, which had been determined as simulans 

 by Uhler, pronounced it "but a clearly marked example of marmoratus," thus rele- 

 gating to synonymy Uhler*s name on color characters alone, without examining his 

 type. Examples of a Stethaulax at hand from Arizona differ distinctly from the 

 eastern form in the following structural characters : Larger, 8.5 — 9 mm. : head longer, 

 more deeply sinuate in front of eyes, less densely punctate above: third antennal longer, 

 subequal to second ; thorax and scutellum much more sparsely and shallowly punc- 

 tate, not alutaceous between the punctures; osteolar canal more slender, its apical 

 portion tapering and slightly curved, its supporting plate very different in sculpture, 

 the punctures being sparse, shallow and ill defined, whereas in the eastern form they 

 are more numerous, deeper and well marked. While Uhler*s original description of 

 his simulans was based mainly on color characters, an exceedingly variable feature 

 in the Scutellerids, it agrees with this western form sufficiently to lead me to be- 

 lieve that it represents his species. At any rate it is very different in the characters 

 mentioned from the eastern marmoratus Say. 



