NATURAL SCIENCES OF PHILADELPHIA. 215 



1. G. externa Say, Journ. Acad. Nat. Sci., Phila., hi. 458 ; ed. Lee, ii. 

 222. Adimonia ext. Lee, ibid. ; G. rudis Lee., Rep. Pacific R. R. Expl., C9. 



Kansas and Oregon ; those from the former locality are more coarsely 

 punctured, hut do not show any specific differences. 



Tke fifth ventral segment in both sexes is marked with two large impres- 

 sions, and in the male is emarginate at tip. 



2. G. crib r at a, ovata, convexa, sordiderufo-testaceanitida, thorace brevi 

 antrorsum angustato, lateribus rotundatis, angulis haud prominulis, basi 

 utrinque oblique truncato, disco haud dense punctato, vage 3-foveato et ad 

 angulos posticos oblique impresso, elytris fortiter cribratim punctatis, sspe 

 vittis angustis tribus utrinque ornatis ; margine laterali fortius refiexo : anten- 

 nis extrorsum infuscatis. Long "21 '28. 



Massachusetts, Georgia, Pennsylvania, Illinois, Kansas. The black vittse 

 are very narrow, and extend from the base almost to the tip ; the outer one 

 is very frequently obsolete, and often all are completely wanting. Sexual 

 characters as in G. externa, except that the impressions of the fifth ventral 

 segment are transverse and smaller. 



3. G. americana Fabr., Syst. El. i. 4S9 ; Oliv., Ent. vi. 636, (No. 93, 

 36,) pi. 3, f. 43. 



Middle States, Illinois, Lake Superior. Of the same form as the preceding, 

 but generally a little smaller, and the elytra are clothed with coarse pubes- 

 cence. The punctation of the elytra is equally coarse, but the sides are not 

 so strongly margined ; the thorax is more punctured, the hind angles are 

 not flattened by oblique impressions, and are somewhat prominent ; the three 

 discoidal impressions of the thorax are fuscous ; the suture of the elytra and 

 three narrow vittse on each are blackish ; the inner one is sometimes obsolete. 

 Last ventral segment with a transverse impression each side ; tip emarginated 

 in the male. 



4. G. conferta, elongato-ovata, minus convexa, sordide testacea haud 

 nitida, thorace brevi antrorsum angustato, angulis haud prominulis, lateri- 

 bus rotundatis, basi utrinque oblique truncato, disco late canaliculato, vage 

 biimpresso, fusco trimaculato, confertim subtilius punctato ; elytris dense for- 

 titer punctatis brevissime parcepubescentibus, fortius marginatis, vittis utrin- 

 que tribus nigris, intermedia postice abbreviata ; antennis fuscis, articulis 

 3 primis testaceo-maculatis ; abdomine fusco, cinereo pubescente. Long *21. 



Canada and Illinois ; two specimens. This species has the elongate form of 

 G. notulata, but is more dilated posteriorly ; the elytra are densely but 

 coarsely punctured, the pubescence is very short, and not conspicuous. The 

 last ventral segment is transversely impressed each side, as in the preceding 

 species. 



5. G. sexvittata, elongata, supra obscure testacea opaca, thorace brevi 

 antrorsum angustato, lateribus rotundatis, angulis haud prominulis, dense 

 minus subtiliter punctato, subcanalioulato, utrinque late impresso, vitta dor- 

 sali maculaque utrinque nigris ; elytris dense punctatis, (punctis antice for- 

 tioribus), vittis utrinque tribus nigris fere integris ornatis ; vitta capitis, auten- 

 nisque nigris, femoribus medio, tibiis apice tarsisque nigris. Long -24. 



One male from Pennsylvania ; the fifth ventral segment is transversely im- 

 pressed each side, and slightly emarginate at tip. _ This species resembles G. 

 conferta, but is more finely and densely punctured. 



Group II. Adimonia p. Laich. 



In two of the species of this group the body is ovate and convex, but in the 

 third the form is elongate ; the upper surface is coarsely punctured, and the 

 pubescence very short and indistinct ; the thorax is deeply channelled, and 



1865.] 



