STUDIES IN THE AMERICAN BUPRESTID^ 1 37 



behind the middle, where they are a third wider than the prothorax, 

 the sides rather rapidly rounding and converging posteriorly, becoming 

 only broadly and very moderately sinuate near the apices; surface 

 very densely but not very coarsely punctato-rugose laterally, very un- 

 even, the punctured areolae much impressed, the striae indistinct and 

 much broken, the callous areas moderately elevated, finely cariniform 

 near the apices; under surface ( 9) as usual, the median tooth of the 

 apical sinus long and slender but obtuse at apex. Length ( 9) 15.0 

 mm.; width 5.5 mm. Iowa ero.sa n. sp. 



Obscura is represented before me by a large series, holding very 

 homogeneously to the characters above stated; cabinet specimens are 

 generally dark and obscure in coloration, but the appearance of fresh 

 examples is markedly different, owing to a pale grayish-metallic 

 bloom which is destroyed unless the utmost care be taken in handling 

 them; it is probably one of these specimens that served as the type 

 of pruinosa. The integuments of the body are so thick and hard that 

 a pin is to be inserted only by using great force; lurida and allied 

 species are not so heavily armored. Soror is compared with obscura 

 by LeConte, and is declared to be identical by Crotch, though the form 

 of the prothorax seems to approximate more closely to that of the 

 lurida type; nothing is stated by the describer regarding the relative 

 size or prominence of the eyes, and I have therefore had to assume 

 that the species will enter the second section of the group. It is 

 entirely possible, however, that this is a mistake and that it is more 

 related to porcalula, in which event regularis will become a true species. 



Group II — Type pugionata Germ. 



This group agrees with the last in nearly all of its characters, includ- 

 ing the unmodified middle tibiae of the male and the deeply sinuate 

 and acutely bidenticulate elytral apices, but here, the latter are more 

 prolonged and the pronotum differs in having a pronounced median 

 impressed channel and subentire smooth sublateral callous vittas, 

 imparting a distinctly different habitus to this part of the body. In 

 pugionata, the elytral tips are as much prolonged as in the next group. 

 The only two known species are the following: — 



Form elongate, the surface golden-brassy in lustre; head densely punctate, 

 with a V-shaped central callus and two on the occiput separated by a 

 moderate channel; prothorax shorter than wide, moderately narrowed 

 anteriorly, the sides anteriorly broadly rounded, the surface conflu- 



