22 



NORTH AMERICAN ANOPLURA 



Hoplopleura trispinosa n. sp. 

 Plate IV, fig. 3, text fig. 8. 



Five specimens, all females, from Sciuropterus volucella (Kensing- 

 ton, Md.) ; Sciuropterus sp. (Eureka, Calif., and Brownsville, Oregon), 

 taken from skins in the Stanford University collection. 



This species is very close to H. arboricola, but is readily distin- 

 guished from the latter by the form of the sternal plate, which is more 

 elongated, and by having six large spines on the first sclerite of the third 

 sternite of the abdomen instead of four. 



hmrri 



Fig. 8. — Hoplopleura trispinosa n. sp. ; ventral side of second and anterior portion 

 of third abdominal segments of female. 



Description of the Female. — Length .J2 mm., length of head .15 

 mm., length of abdomen .55 mm., width of head .1 mm., width of abdo- 

 men .4 mm., width of thorax .2 mm. 



Head pointed anteriorly, temporal angles prominent, temporal mar- 

 gins nearly straight, forming a very slight angle with the occipital mar- 

 gin, which is produced into a point. A brown chitinized area on each 

 side just in front of the antennae. Several small hairs on the anterior 

 margin, three or four on the temporal margin, and one long hair and a 

 short spine at the posterior lateral angle. A distinct transverse suture 

 just behind the antennae. Antennae with the first segment large ; second 

 segment about as long as the first but much more slender ; third, fourth 

 and fifth segments shorter, subequal. 



Thorax hexagonal in shape, wider than long, the posterior margin 

 of the prothorax with a hair on each side just within the spiracle. Stern- 

 al plate triangular, lateral margins longer than the anterior margin. Legs 



