1911] Promachiis and Proctacanthus 161 



pollinose, dorsum of the mesothorax and scutellum with pale bristles; 

 wing clear hyaline, veins pale brown; legs rather light colored, femora 

 darker before than behind, all parts of the legs with black bristles and 

 pale hair. Hair and bristles of all parts of the abdomen gray. Male 

 genitalia about as long as the last two abdominal segments, female 

 genitalia with a circlet of strong spines at the tip. 



The rather small size of the species, with the white bristles 

 of the whole body, especially the scutellum, and the general 

 pale color are distinctive. 



Male type and numerous other specimens taken along the 

 Ohio River in Ohio and Kentucky by Charles Dury for 

 whom the species is named. 



Proctacanthus arno Townsend. 



Total length 2S to 3G millimeters. Mystax white, usually with a few 

 black bristles beneath, beard white, palpi black with black and white 

 hairs, proboscis black, occipito-orbital bristles partly black and partly 

 white, whole body grayish brown pollinose. Thorax with the usual 

 markings above, mesothorax above with short black hairs anteriorly 

 and rather stout black bristles posteriorly, scutellum with many black 

 bristles and a few white hairs anteriorly. Legs in general color rather 

 dark, femora nearly black before, brown behind, tibiae and tarsi some- 

 what variable but often quite dark so that they show no contrast with 

 the femora; wings hyaline, usually with the veins faintly margined 

 with brown, but in teneral specimens they are entirely glassy clear. 

 Abdomen rather slender, male genitalia elongate, longer than the last 

 two abdominal segments, appendages from side view, narrowest at the 

 middle, slightly widened and curved inward at the tips so that from 

 dorsal view a distinct open space is enclosed beyond the other genital 

 parts. Female genitalia usually shining black with short white hairs, 

 end piece rather sparsely hairy with a circlet of strong black spines at 

 the tip. 



The long male genitalia as described characterizes this 

 species fully. 



The type was collected at the southern end of Lower Cali- 

 fornia. Specimens are at hand from southern Arizona, New 

 Mexico, Utah, Palo Alto, California, and El Paso, Texas. 



Proctacanthus nigrofemoratus n. sp. 



Total length of the male type 30 millimeters, other specimens vary 

 from 23 to 30 millimeters. Mystax beard and hair of the palpi white; 

 palpi, antennae and proboscis black; occipito-orbital bristles partly 

 black and partly white. Thorax gray pollinose, mesothoracic dorsum 

 with black hairs and bristles, scutellum with black bristles; wings 

 hyaline with pale veins. Femora uniformly black all over, tibiae pale 

 on the basal parts, otherwise dark, nearly black, as are all the tarsi. 



