Between August 1952 and February 1954, while Washington, vol. 54, pp. 176-177; 1953, Proc. Ent. Soc. Washington, vol. 55, p. 180; 1954, Bull. Brooklyn Ent. Soc, vol. 49, pp. 3-4; and 1954, Proc. Ent. Soc. Washington, vol. 56, p. 230. This paper completes a taxonomic revision of the Nearctic Psammocharidae, other sections of the family having been treated as follows:Aporini by Bradley, 1944, Trans. Amer. Ent. Soc, vol. 70, Psammocharini by Evans, 1950 and 1951, Trans. Amer. Ent. Soc, vol. 75, vol. 76, and vol. 77,. Pejpsis by Hurd, 1952, Bull. Amer. Mus. Nat. Hist. vol Figure 1, Chirodamus pyrrhotnelas 9 ; 2, Pepsis thisbe 9 ; 3, Hemipepsis usiulata ochroptera 9 ; 4, Priocnessiis nebulosus 9 ; 5, Priocnemioides austrinus austrinus 9 ; 6, Cryptocheilus idoneum birkmanni 9 ; 7, Priocnemis (Priocnemissus) minorata 9 ; 8, Calicurgus hyalinatus alienatus 9 ; 9, Dipogon (Deuteragenia) sayi sayi 9 ; 10, Dipogon (Dipogon) brevis brevis 9 ; 11, Auplopus nigrellus 9 ! 12, Notocyphus dorsalis arizonirus cT; 13, Minagenia clypeata 9 ; 14, Cernpales maculata fraterna 9 • Plate 2 Figure 15, Chirodamus maculipennis 9 ; 16, Priocnessus apache 9 ; 17, Priocnemioides angusticeps 9 ; 18, Priocnemioides unifasciatus unifasciatus 9 ; 19, Priocnemioides unifasciatus californicus 9 ; 20, Cryptocheilus terminatum lerminatum 9 ; 21, Priocnemis (Sphictostethus) pretiosa 9 ; 22, Priocnemis {Priocnemis) germana 9 ; 23, Priocnemis {Priocnemis) scitula scitula 9 ; 24, Priocnemis {Priocnemis) hestia 9 ; 25, Priocnemis {Priocnemis) minuscula^; 26, Dipogon {Deuteragenia) pulchripennis 9 ; 27, Dipogon {Deuteragenia) papago anomalus 9 ; 28, Dipogon {Deuteragenia) sayi nigrior 9 (type); 29, Dipogon {Dipogon) graenicheri atratus 9 (type); 30, Auplopus architectus architectus 9 ; 31, Ageniella {Priophanes) facetafaceta 9 ; 32, Ageniella {Ageniella) conflicta 9 ; 33, Ageniella {Ageniella) accepta 9 ; 34, Ageniella {Ageniella) blaisdelli To my wife goes special acknowledgement for the many ways in which she assisted with this study, particularly in recording distributional data and preparing the maps. The maps are intended to give a quick comprehension of the known distribution, with a spot for each definite locality. Indefinite localities, hke a state, or localities not in the atlases at hand, could not of course be indicated by definite spots and so had to be omitted. They are included, however, in the lists of specimens studied.
TenninologyThe Rohwer and Gahan (1915, Proc. Ent. Soc. Washington, vol. 18, pp. 20-76) system of wing vein and ceU terminology is used.This terminology is explained in figure l,a.The subgenital plate is the last visible sternite-the apparent seventh but actual eighth ( subcostella; 19, mediella; 20, submediella; 21, metacarpella; 22, radiella; 23, cubitella; 24, discoidella; 25, intercubitella; 26, nervellus. The sharp transverse groove on the second sternite of all females (fig. l,c) and some males is the easiest recognition mark.Some members of the other two subfamilies have a broad, weak, tra...