NATURAL SCIENCES OP PHILADELPHIA. 217 



11. G. marginella Kirby, Faun. Bor. Am. iv. 220; ?G. luctuosa 

 Mannh., Bull. Mosc. 1S65, 368 ; ibid. 1853, 259. 



I refer a specimen of narrow form, and -25 uno. long., from Fort Simpson, 

 Hudson Bay Territory, to this species. It differs from the next by its more 

 elongate form and scarcely prominent anterior angles of the thorax. The 

 body beneath is black, clothed with silvery hairs, legs brown, tibiae and tarsi 

 paler. This species should probably not be separated from G. nymphsse 

 Fabr, Ent. Syst.. i. 2, 21 ; Syst. EL, i. 486. Oliv. Ent., vi. 643, (No. 93, 49,) 

 pi. 3, fig. 51, &c, &c. Chrysomela nymphaxe Linn. 



12. G. sagittarise Gyll., Ins., iii. 511, &c, &c. Redt., Fauna Austr., 

 2d ed., 928. 



Found throughout the middle and northern parts of the Atlantic district. 

 I refer to this species the rather stoutly-formed specimens with punctured 

 elytra and well marked sutural angle, which occur abundantly on Nym- 

 ph ?e a and N u p h a r ; the prothorax is polished, with scattered large punc- 

 tures ; the dorsal channel is well marked, and the two discoidal excavations 

 large and deep ; the sides are subangulated, and the anterior angles promi- 

 nent ; the base is obliquely truncate each side, as in the two preceding spe- 

 cies ; the disc is yellow, usually with three large blackish spots. The pubes- 

 cence of the elytra is very short, and the margins yellow-testaceous. The 

 under surface is dusky, the tip of the abdomen pale ; the logs testaceous, with 

 part of the thighs and outer portion of tibia? and tarsi dusky. 



The last ventral segment of the male is deeply and acutely emarginate. 



13. G. decora, longiuscula, fusca vel picea, dense sericeo-pubescens, 

 thorace opaco, subtiliter dense punctato, canaliculato, utrinque late foveato, 

 lateribus late rotundatis, augulis omnibus valde prominulis, basi utrinque 

 oblique truncato, elytris baud dense punctatis, angulo suturali apice rotun- 

 dato ; subtus nigro-picea, pedibus obscure testaceis. Long. "19 '21. 



Say, Long's Exp. St. Peter's, ii. 294 : ed. Lee. i. 195. 



Abundant at Lake Superior, Slave Lake, and in Canada ; found also in 

 Mass. and Illinois. 



This species varies considerably in color and sculpture ; the lighter-colored 

 specimens have the thorax yellow with three black spots, and the elytra 

 margined with yellow ; the thoracic angles are usually very prominent, but 

 sometimes are less conspicuously so ; the elytra are sometimes very strongly 

 and uniformly punctured : sometimes the punctures towards the tip are less 

 impressed. I have not been able to discover any constant differences sufficient 

 to lead to a division of the species into races. 



The fifth ventral segment of the male is deeply excavated, the margin of 

 the excavation being acute and elevated, almost as in G. hseruati c a. 



14 G. c arbo Lee, Proc. Ac. Nat. Sci. Phila., 1861, 358. 



Oregon, east of Fort Corlville, G. Gibbs, Esq. Only differs from the preceding 

 by the color, which is entirely black. It should probably be considered as a' 

 race of G. decora. 



15. G. notulata Fabr., Syst. El., i. 439; Oliv. Ent., vi. 636, (No. 93, 

 37,) pi. 3, fig. 44. 



Found throughout the Atlantic district. Of the same form and sculpture 

 ^s G. decora, but differing in color, which is dirty testaceous above, with 

 an occipital line, three thoracic spots, and four narrow lines on each elytron 

 black ; the subsutural vitta extends from before the middle nearly to the tip, 

 where it unites with the submarginal one ; the second vitta is oblique, and 

 becomes confluent with the subsutural one behind the middle. 



I think that G. bilineata Klrby, Faun. Bor. Am., iv. 220, is a specimen 

 of this species with indistinct markings. 



The fifth ventral segment is impressed transversely each side in both sex, 

 and is tolerably strongly emarginate at tip in the male. 



1865.1 



