CHAMBERLIN: HENICOPIDAE OF AMERICA NORTH OF MEXICO, y 



i 



caudal corners rounded. Ninth and eleventh plates with caudal 

 corners obliquely truncate or excised; caudal margin of thirteenth 

 plate straight. 



Ventral plates rugose and uneven; on most a deeper furrow parallel 

 with and not far from the anterior margin and a similar one toward 

 caudal margin, the two on anterior plates often united at ends by 

 longitudinal furrows and thus forming a large rectangular impression. 



Twelfth to fifteenth pairs of legs without tibial process. Tarsi 

 of last three pairs of legs distinctly biarticulate; those of the immedi- 

 ately preceding legs often showing a suture faintly developed. All 

 others with tarsi strictly undivided. 



Anal legs short, about equalling the antennae, the body being thus 

 near 3.5 times longer. Tibia mostly between 3 and 3.5 times as long 

 as thickness dorsoventrally; first tarsal joint four times as long as 

 dorso ventral thickness; the second tarsal joint 4.6 times longer than 

 thick. Length of anal legs to that of the penult about as 4:3. 



Coxal pores small, circular; mostly 2, 3, 3, 3, occasionally 2, 4, 4, 4. 

 Each pore bearing coxa commonly with a longer bristle at distal 

 ventral edge. 



Gonopods of female sparsely pilose; claw long, acute, and entire, 

 moderately bent and with concave side excavated; basal spines 2+2 

 (with rarely an extra one on one side), conical with one or both of 

 each pair often bent ectad at tip. 



Length 7-11 mm., but mostly 7-9 mm. 



Agenitalis. Very pale yellowish brown, with a violet tint showing 

 through from the tissues beneath chitin; head yellowish with the 

 region of eyes and apex of head darkened. 



Ocellus very distinct. 



Antennae composed of 21 to 23 articles. 



Prosternal teeth 3+3, the outer one on each side minute. 



Coxal pores 1, 1, 1, 1. 



Gonopods extended but showing no trace either of claws or of basal 

 spines. 



Length 4.5-5 mm.; greatest width .6-. 7 mm. (Latzel). 



TYPE LOCALITY. Europe. 



NORTH AMERICAN LOCALITIES. Maine (Orono!); Massachusetts 

 (Cambridge!); New York (New York City at Mt. Lebanon); Penn- 

 sylvania!; Wisconsin (Haugen! Eau Claire! Ashland! Beloit! Meno- 

 minee!); Michigan (Powers! Watersmeet! Marinette!); Illinois 

 (Peoria!); Minnesota (Winona); Nebraska (Omaha!); Colorado 

 (Colorado Springs!); Utah (Lake Point! Salt Lake City! East Mill 



