194 REVISION OF THE BUPRESTID OF THE UNITED STATES. 
may be isolated by characters to form a group of lower value than the three into which I 
divide the genus, and which may be thus distinguished. 
A. Corpus elongatum, elytris oblique attenuatis et preecipue valde prolongatis, apice seepissime integris; pros- 
terno metasterno et abdominis segmento primo late sulcatis; mesosterno haud punctato; antennis articulis 2 et 3 
zequalibus. Mares segmento ventrali ultimo truncato emarginato, tibiis intermediis intus late emarginatis, et 
supra medium dente magno armatis. Feminz segmento ventrali rotundato, acute biinciso. 
a. Elytra apice integra; abdomen art. ult. ventrali canaliculato lineis duabus levibus munito. Sp. 1-3. 
b. Elytra apice bidentata; abdomen art. ult. vix canaliculato - - - Sp. 4. 
B. Corpus elongatum, elytris oblique attenuatis paulo vel vix prolongatis, apice bidentatis (excepta spec. 4,) 
abdominis segmento 1mo plus minusve sulcato; mesosterno haud vel vix punctato; antennis articulo 2ndo breviore. 
Mares segmento ventrali ultimo truncato emarginato, tibiis intermediis seepissime intus late emarginatis et supra 
medium dente armatis. Femine sicut in A. 
* Frons haud transversim carinata. 
c. Metasternum sulcatum. 
a. Prosternum convexum. - - - - - - Sp. 5. 
B. Prosternum sulcatum. - - - - - - Sp. 6—9. 
d. Metasternum haud sulcatum. - - - - = - Sp. 10—11. 
* > e Frons inter antennas transversim carinata. - - - - - Sp. 12. 
©. Corpus crassiusculum, elytris oblique magis abrupte attenuatis et breviter prolongatis, integris vel vix biden- 
tatis; antennis articulo 2ndo breviore. Sexus differentia varia. 
* Abdomen segmento ventrali ultimo haud costato. 
f. Sternum late sulcatum, mesosternum rude punctatum, (abdominis segmento ultimo maris truncato 
emarginato. ) - - - - - - - - Sp. 183—15. 
g. Sternum parum sulcatum, mesosternum parce punctatum (abdominis segmento ultimo maris?) Sp. 16-17. 
h. Prosternum planum cum mesosterno dense punctatum, (abdominis segmento ultimo feminze rotundato, 
maris truncato. ) - - - - - - - - Sp. 18-20. | 
i. Sternum valde sulcatum, mesosternum parce punctatum, (abdominis segmento ultimo maris rotundato ) 
Sp. 21—22. 
* * k, Abdomen segmento ultimo acute bicostato, (maris truncato, haud emarginato.) Sp. 23. 
A.—a. 
1. D. prolongata, griseo-genea, seepe pruinosa, thorace latitudine plus duplo breviore, lateribus antice valde 
rotundatis postice subsinuatis, punctato, canaliculato, utrinque pone medium oblique profunde impresso; elytris 
striis profundis, interstitiis spatiis cblongis obscurioribus levibus parum elevatis, postice oblique attenuatis, pro- 
longatis, apice rotundatis vix divaricatis; subtus parce pubescens. Long. -77—-85. 
Lake Superior, Nebraska, and Wisconsin. From the other species of this group, it differs 
by the thorax being shorter, much narrower and more rounded in front, more punctured, 
and with the dorsal channel and oblique impressions, more strongly marked. As in the 
neighbouring species, the pro- and metasternum, and first ventral segment are broadly and 
deeply sulcate, and the divided mesosternum very sparsely punctured: the last ventral 
segment has two smooth longitudinal spaces. The last ventral segment of the male is 
