56 Trans. Acad. Sci. of St. Louis. 
. Legs very long, hind pair at least twice as long as the body 3..° 
Legs much shorter, hind pair never one and a half times as long 
as the body 4, 
3. Thumbs enormously swollen, being much broader than segment four 
of the palpus R. pollicaris. 
Thumb moderately swollen, equal to segment four in width 
R. parvisetosus. 
bo 
4. Palpi twice as long as the mandibles 5. 
Palpi subequal or but slightly longer than the mandibles 8. 
5. Tarsus of leg I longer than the tibia R. longitarsus. 
Tarsus of leg I not longer than the tibia 6. 
6. Tarsus of tibia of leg I subequal in length R. erythreus. 
Tarsus of leg I much shorter than the tibia 7. 
7. Tarsus of leg I not swollen R. quadrioculus. 
Tarsus of leg I quite swollen R. brevitarsus. 
8. Integument of body with many small black spots R. leprosus. © 
Integument of body without spots R. parvipollicus. 
Rhyncholophus tridentifer n. sp. 
Pl. VIII. f. 2-3. 
Light red; appendages much paler than the body. Body well clothed 
with peculiar hairs or bristles. Each hair consists of three long prongs 
united at the base in such a manner as to form a trident; prongs of the 
trident equal, curved inward and pectinate on their outer margins. 
Cephalothorax much reduced, about as broad as long. Palpi about 
one half as long as the anterior pair of legs; thumb small, not swollen, 
extending to the tip of the palpal claw; palpal claw about as long as the 
segment from which it extends, slightly curved; second segment of the 
palpus the largest, about one-half as broad as long. Mandibles two- 
thirds as long as the palpi. Dorsal groove extending the entire length 
of the cephalothorax with a circular expansion at about one-third its 
length from the posterior end; a long thread-like pair of hairs situated 
on this circular expansion which are about one-half as long as the 
groove itself. A single pair of eyes situated upon an oblong elevation 
about half way between the dorsal groove and the lateral margin of 
the cephalothorax. 
Abdomen long, swollen in front between the first and second group of 
legs. 
Anterior pair of legs about two-thirds as long as the body; tarsus 
longer and broader than the tibia; tibia and antepenultimate segment 
subequal. Second and third pair of legs subequal; hind pair of legs 
equal to the anterior pair and extending slightly beyond the posterior 
margin of abdomen. Tarsus and tibia of the last pair of legs subequal. 
All the legs well clothed with bristles. 
Length, 0.90 mm.; breadth, 0.48 mm. 
Common under the bark of soft maple trees an some- 
times found under the bark of other trees. Collected by 
J. D. Hood at Urbana, IIl., and by the Wihlaaes at Arcola and 
Muncie, Ill. 
