Apidae — Sphecodinae. I55 



except sometimes at the base. It differs from all of the other species, 

 and from all of the Halictinae, from the fact that the male appears 

 in spring with the female. 



In the second group, in which the male has the fourth Joint of 

 the antennae hardly longer than the third, the species whose females 

 have the mandibles dentate are referred to the new genus Sphecodium, 

 with Sphec. cressonii sp. nov. as the type, and those with simple man- 

 dibles are referred to Machaeris gen. nov., type Sphec. stygius having 

 the vein represent and the clypeus convex, and Dialonia gen. nov., 

 type Sphec. antennariae, having that vein absent and the clypeus 

 flat or a little concave." 



In seinen Tabellen, die ich nachfolgend bringe, fehlt beim $ voll- 

 ständig die Untergruppe Sphecodes s. str., die er nur beim (^ anführt : 



Females. 



Mandibles yellowish or reddish, the tip darker; small or middle 

 sized 3. 



Mandibles rufous, base usually largely black; large or middle 

 sized 1. 



1. Mandibles simple; labrum long, strongly notched; mesonotum 

 closely punctured; segments 4- — 5 more or less black; vein rm. short 



Drepanium falciferum. 

 Mandibles dentate; labrum short, rounded or truncate 2. 



2. Joint 4 = 2 + 3, or nearly; abdomen narrow, evenly, coarsely, 

 distinctly punctured, entirely red, segment 5 = 4, or longer ; clypeus 

 f inely and densely punctured ; mesonotum coarsely and closely punctiu:ed 

 cell III 5 strongly narrowed above. Proteraner ranuncuU. 



3. Mandibles dentate Sphecodium. 

 Mandibles sim.ple 4. 



4. Vein rm. wanting; clypeus short, flat; mandibles long; meso- 

 notum shining, greenish, finely and sparsely punctured; metathorax 

 short, encloBure poorly defined, with longitudinal raised lineß. 



Dialonia antennariae. 

 Vein rm. present; clypeus longer, more convex. Machaeris. 



Males. 



Joint 4 longer than 2 + 3, which are equal ; abdomen red, except 



sometimes at base, apex broadly rounded Proteraner ranuncuU. 



Joint 4 hardly longer than 3 2. 



Joint 4 about equals 2 + 3 1. 



1. Joint 3 twice as long as 2; flagellum notched beneath twoards 

 apex; mesonotum closely punctured; mandibles red; vein rm short, 

 abdomen black, segment 7 red, at least at apex. Drepanium falciferum. 



Joint 3 not twice as long as 2; vein rm little shorter than III 5. 



Sphecodes. 



2. Clypeus flat or a little concave ; vein rm wanting ; metathorax 

 ßmooth, shining, with some longitudinal raised lines. 



Dialonia antennariae. 

 Clypeus convex; vein rm usually present. 



Sphecodium or Machaeris. 



1. Heft 



