i9. 6 Rohwer : Wasps of Subfamily Sphecinse 673 
Described from one female received from C. F. Baker, for 
whom the species is named. 
Tribe SCELXPHRONINI 
Genus SCELIPHBON Klug 
Many authors have considered that all the species belonging 
to this genus should be referred to one superspecific group, but 
I am inclined to agree with Dahlbom, Patton, and, others and 
recognize two subgenera separated by certain structural charac- 
ters and easily distinguished by color. Patton 2 was the first 
to point out the structural characters and at that time he used as 
genera the names Pelopaeus and Chalybion. Since then the blue 
species have usually been referred to Chalybion. Hutson 3 ex- 
presses the belief that this is wrong and that the name Sceliphron 
will have to be used for the metallic forms. He bases his opinion 
on recommendations k and n of the International Commission on 
Zoological Nomenclature and overlooks the designations of geno- 
types made by previous students. In 1810 Latreille designates 
the type of Pelopaeus as spirifex and in 1897 Bingham cites 
the same species as the type of Sceliphron . The species spirifex 
was included in the original account of both these genera, and 
both of the above type designations must be accepted as valid 
even if Bingham did not follow the recommendations (he violated 
no rules) of the International Code. Sceliphron Klug and Pelo- 
paeus Latreille are isogenotypic and since Sceliphron is the older 
name Latreille’s name will have to be placed in synonymy. This 
makes it possible to retain the name Chalybion for the metallic 
species. 
Key to the subgenera of Sceliphron. 
Black and yellow species; petiole usually about twice as long as propodeum; 
clypeus bilobed or bidentate anteriorly Sceliphron Klug. 
Metallic blue species; petiole subequal with the propodeum; clypeus with 
more than two teeth Chalybion Dahlbom. 
Subgenus Chalybion Dahlbom 
The only species of this genus was originally described under 
the name bengalensis by Dahlbom and considered to be different 
from the European form, but more recent authors have synon- 
ymized the two and I have followed them. 
2 Proc. Boston Soc. Nat. Hist. 20 (1880) 378. 
8 Trans. Am. Ent. Soc. 45 (1919) 218. 
