40 



BULLETIN" 15 8, UNITEt) STATfiS NATIONAL MUSEUM 



Color. — Female transparent, with large orange or brick-red spot 

 in the posterior part of the thorax ; the long bristles and the terminal 

 segment of the first antennae are bright orange ; the broad plumes at 

 the base of the first antennae and on the caudal rami are brownish 

 red, with a brilliant metallic iridescence ; eye bright red. The body 

 of the male is transparent, with a greenish-yellow wash ; the terminal 

 two-thirds of the first antennae and all their plumes, the long, narrow 

 bristles of the second antennae, mandibles, and caudal rami are bright 

 red ; eye minute and ruby red. 



Female. — Urosome 2-segmented; genital segment onion-shaped; 

 caudal rami turned outward until they stand in the same straight 

 line at right angles to the body axis; each ramus armed with four 

 enlarged plumes, which can be spread or folded at will. Distal endo- 



FiGURB 22. — Calocalatius pavo: Female, dorsal. (From W. M. Wbeeler) 



pod segment of third and fourth legs with a cluster of small spines; 

 fifth legs 4-segmented, the terminal segments with four or five 

 plumose setae on the inner margin and at the tip and a single spine 

 at the outer distal corner ; this segment also has two rows of spinules 

 across its anterior surface near the tip. Total length, 0.8-1.25 mm. 

 Male. — Head more or less separated from the first segment ; fourth 

 and fifth segments fused, with sharp posterior corners; urosome 

 5-segmented; caudal rami parallel with the body axis, the plumes 

 slender and incapable of spreading or folding ; right fifth leg 4-seg- 

 mented, its tip only reaching the middle of the second segment of 

 the left leg; the latter 5-segmented, a large spine at the inner distal 

 corner of the fourth segment and two much smaller ones at the tip 

 of the end segment. Total length, 1-1.15 mm. 



