198 University of California Publications. [ ZooLocy 
distinguishing the species at once. Appendages colored about as 
in the other forms. 
Length: Female 2.9 mm, male 2-2.5 mm. 
Occurrence: Several males and females were taken October 
20, 1904. 
Fam. PONTELLIDAE. 
Pontellidae Giesbrecht, 1892, p. 68; 1898, p. 131. 
2 Head and thorax distinct, fourth thoracic segment usually 
fused with fifth. Rostrum forked, usually ending in two very 
strong prongs; rarely absent. Eyes large, sometimes with one 
or two pairs of cuticular lenses and one unpaired lens. Anterior 
antennae 16- to 24-jointed, the two terminal joints always fused. 
Second basal and first joint of inner ramus fused, terminal joints 
of outer ramus shortened. Mandible on the whole as in the 
Centropagidae. First basal of maxilla large, -second basal and 
rami relatively small. Anterior maxillipeds as in the Centro- 
pagidae, long, hooked bristles on distal portion and commonly 
on the proximal. First basal of posterior maxillipeds large with 
long bristles on lobed inner border, second basal and inner ramus 
relatively small. Inner ramus of four anterior pairs of feet or 
second to fourth, 2-jointed; fifth pair rudimentary, outer ramus 
1-jointed (rarely 2-jointed), inner ramus 1-jointed or lacking. 
3 Distinct from female in form of abdomen, anterior 
antennae and fifth pair of feet, at times also in form of eyes, 
rostrum and last thoracic segment. Genital orifice on left side, 
erasping antenna on right, middle joints much or slightly 
broadened; joints 19 and 21 and 22 to 25 fused. Fifth pair of 
feet rarely with rudiment of inner ramus; forceps of right foot 
incomplete or very powerful. 
Sub-fam. PONTELLINAE. 
Pontellina Giesbrecht, 1892, p. 68. 
2 Cephalothorax with five or six segments; last thoracic seg- 
ment ends in one (seldom two) sharp points on each side and is 
at times asymmetrical. Rostrum ends in two strong chitinous 
prongs or in two filaments. One pair of cuticular lenses is 
occasionally found on the dorsal side, seldom two pairs, ventral 
