S PROCEEDINGS OF THE NATIONAL MUSEUM vol.71 



clypeus does not extend far below a line drawn between the 

 bottoms of the eyes; the petiole is usually shorter than in the male, 

 and the end of the abdomen is conical. 



Hairs may differ in color in the sexes. In some cases the head 

 and body hairs in the female are all black while in the males white 

 hairs occur. In this case they first appear near the hind end of the 

 thoracic mass, then spread forward along the sides of the thorax to 

 the pronotum and even onto the vertex and cheeks on the head. 

 Oftentimes the hairs behind may be entirely white; further forward, 

 black or brown with white tips; and black further forward. 



Males nearly always have more black on their bodies than the 

 females. The male Podalonia valida has the tip of the abdomen 

 black. 



GEOGRAPHICAL DISTRIBUTION 



Species of this genus occur in Europe, Asia, Africa, Australia ? {sus- 

 piciosa Smith), South America {hocandei Spinola), and North Amer- 

 ica. In the last-named country I have examined specimens from as 

 far north as Nova Scotia and Fort McLeod, British Columbia (about 

 latitude 5.5°), and several species occur in different parts of Canada. 

 Southward they are found in all parts of the United States, in Mex- 

 ico and to Panama though the records of these southern forms (Bio- 

 logia Centrali-Americana) suggest that in Central America they are 

 mainly inhabitants of elevated districts. 



In North America some species are widely distributed; others 

 rather local. Details of distribution are given in connection with the 

 individual species. Maps illustrating the known distribution of four 

 of the more widely distributed species are included as text figures. 

 In these maps the solid black dots stand for actual locality data, 

 while the cross (x) indicates specimens for which only the state was 

 given. 



CLASSIFICATION 



One not familiar with the insects of this group will find keys by 

 which they may be traced to the Sphecidae in Comstock's Introduc- 

 tion to Entomology, First Complete Edition, 1924, and on page 963 

 of that book is a further key leading to the subfamily (there errone- 

 ously called tribe) Sphecinae. On page 966 is a brief treatment of 

 the subfamily, but without further classification. 



In a previous paper ^ on another section of this subfamily, the 

 group was considered by me as a family and its divisions were called 

 subfamilies. In my opinion this is a better valuation than that given 

 by Comstock, but to produce continuity in the keys and avoid con- 

 fusion, the key below accepts Comstock's terms and divides the sub- 



J Proc. U. S. Nat. Mus., vol. 31, p. 295. 1906. 



