1911] Promachus and Proctacanthus 163 



Related to philadelphicus but the pale hairs of the palpi, 

 long, wide wings and more grayish pollinosity of the body 

 serve to characterize it. 



Proctacanthus craverii Bellardi reported from Mexico, 

 from the description, I take to be a synonym. 



Specimens at hand from Georgia, Florida and Texas. 



Proctacanthus milbertii Macquart 



Total length 2S to 40 millimeters. Mystax pale yellow, beard paler 

 than the mystax, palpi black with black hair. Thorax gray pollinose, 

 mesothoracic dorsum with the usual markings rather plainly shown, 

 scutellum with black bristles and usually with a few pale hairs; wings 

 uniformly light brown; legs brown, tibiae and tarsi lighter than the 

 femora which are darker anteriorly than behind. Abdomen gray or 

 in some cases brownish gray pollinose. Male genitalia shorter than the 

 last two abdominal segments combined, appendages not curved toward 

 each other at the tips; ovipositor usually black but occasionally red or 

 partly red, with a circlet of strong spines at the tip. 



Related to philadelphicus, but the mystax and wings are 

 paler; the abdomen is gray and not brown pollinose and the 

 thoracic markings are rather more distinct. 



Specimens from western Ohio, Indiana, Wisconsin, Kansas, 

 Missouri, Michigan, Colorado, California and British Colum- 

 bia. It is one of our most common and widely distributed 

 species. 



Under the name Asilus missouriensis, Riley has written of 

 this species as a distinct enemy of bees. 



Proctacanthus nigriventris Macquart. 



Total length 30 to 35 millimeters. Body very dark, nearly black; 

 wings uniformly rather pale brown. Mystax very pale yellowish, often 

 with black bristles intermixed, beard gray, occipito-orbital bristles 

 black. Thorax dark, brown pollinose, mesothoracic dorsum with 

 black hair and bristles, usual markings not plainly differentiated; scu- 

 tellum with black hairs and bristles. Wings uniformly rather pale 

 brown, legs dark nearly black; femora, except the apices, black, apexes 

 of femora, tibiae and tarsi dark brown. Abdomen dark, nearly black, dark 

 pollinose with a narrow band before each incisure light pollinose, venter 

 and sides of the last two or three segments in the male gray pollinose; 

 male genitalia dark red, rather short, appendages widest at the base, 

 gradually narrowed toward apex where they are evenly rounded; 

 ovipositor shining black with strong black spines at the tip. • 



The very dark color of the whole body is distinctive. 

 Specimens from New Jersey, collected by H. S. Harbeck, of 

 Philadelphia. 



