370 



PROCEEDINGS OF THE ACADEMY OF 



** Front margin of mesosternum trilobed, with an oblique impression each 

 side. 



5 — 6 mm. Oval, shining black, highly polished, margins and sides bronzed ; 

 elytra at tip moderately rounded ; outer angle not distinct ; rows composed of 

 bronzed, approximate punctures, outer rows not stronger than the inner ones; 

 beneath black, slightly bronzed ; legs ferruginous, thighs darker. (Of the same 

 size and form as G. 1 i m b a t u s and consobrinus, but easily recognized 

 by the very peculiar form of the mesosternum.) 20. p e ct or al i s, n. sp. 



b. Body broader, subovate, more suddenly convex at the middle and 

 obliquely declivous before and behind. 



5-5 mm. 9- Uniform black, bronzed above; elytra with the tip broadly 

 truncate, feebly rounded, outer angle distinct but rounded ; rows composed of 

 fine approximate punctures, outer ones not stronger, lateral margin more 

 broadly reflexed than usual. Beneath black, with slightly metallic reflection, 

 last ventral segment dark brown, legs ferruginous ; mesosternum feebly chan- 

 neled for its entire length 21. gibber Zim. 



B. 



4 — 4-5 mm. Elongate oval, bluish black, not highly polished, sides broadly 

 bronzed ; elytra with the tip truncate, feebly rounded, outer angle somewhat 

 distinct, though rounded ; rows composed of approximate bronzed punctures, 

 the outer ones stronger than the inner; under surface, inflexed margins and 

 legs ferruginous, anterior ventral segments sometimes darker ; mesosternum 

 with a very deep median furrow 22. minutus Linn. 



3-5 — 4-5 mm. Of the same size and form as minutus, but a little 

 narrower and more convex and of a more dull black color, though slightly 

 bronzed at the sides ; prothorax more rugose, rows of the elytra composed of 

 more approximate punctures, and especially distinguished by the mesoster- 

 num being but feelDly channelled in front, with a large elongate posterior 

 fovea ; under surface always ferruginous yellow. 



23. rockinghamensis Zim. 



Bibliography and Remarks. 



1. G. confinis. Similar in form to the Californian G. consobrinus, but 

 less polished, with a slight bronzed color over the whole upper surface, more 

 brilliant at the suture and margins. Abundant at Lake Superior. I have 

 also several specimens from the interior of Oregon or Montana. 



2. G. fraternus Couper, Canadian Naturalist, 2d ser. ii, 60. Canada 

 and Lake Superior ; for types I am indebted to Mr. W. Couper, late of Quebec, 

 but now of Ottawa. Is of the same size as the preceding, but a little more 

 robust, and easily distinguished by the entire absence of bronzed lustre on 

 the upper surface, even at the suture and margin. 



3. G. limb at us <?«?/, Trans. Am. Phil. Soc. ii, 109; ed. Lee. ii, 520. 

 Canada and Lake Superior. In one specimen the suture is not bronzed, and 

 in one the abdomen is dark brown at the middle. I received from the late 

 Dr. T. W. Harris a specimen of this species from Western New York, as No. 

 1642^of his collection, G. analis Say, and in Dr. Zimmermann's collection it is 

 named G. limbalus Say. From the former it differs by the under surface being 

 ferruginous. It is quite possible that the determination of Dr. Zimmermann 

 is correct, and although I have seen no specimens from Georgia and 

 Florida, the locality mentioned by Say, I have no other which agrees 

 so nearly with his description, or which resembles in appearance G. analis, 

 with which he compares it. 



4. G. a e n e o 1 u s. One specimen, Illinois, Mr. Willcox. This species is 

 easily known by the uniform and tolerably brilliant bronze color of the upper 

 surface, which, with the more elongate form and ferruginous under surface 

 perfectly defines it. 



[Dec. 



