54 | Trans. Acad. Sci. of St. Louis. 
In this paper 32 species are described, which are dis- 
tributed in 14 genera and 7 families. The arrangement 
into genera and families is as follows: 
CHEYLETIDAE GAMASIDAE 
CReptete oo es 1 species. Hy letaetes oo. ces 1 species. 
COTGBUE ea ee 3 species. 
seoRe GRANT 9 : UROPODIDAE 
. bionscade tiles aaa ; pt, Weta sin TrOBOdt ccc dee 5 species. 
seta tanesidl azn ty der los Rene CFPORERUE i os 1 species. 
TRAYCIAS 5S  iaek 1 species. 
TROMBIDIIDAE OSTA RE 
Trombidium.......+.. 2 species. ; 
# OniDehe ee oR 1 species. 
GAMASIDAE TYROGLYPHIDAE 
Macrocheles .......... 2 species. Tyroglyphus......... 1 species. 
POAS so ON eek 3 species. Rhizoglyphus........ 1 species 
DESCRIPTION OF SPECIES AND HIGHER GROUPS. 
CHEYLETIDAE. 
Body divided into cephalothorax and abdomen; last segment of palpus 
transformed into a papilla, while the penultimate ends in a large claw; 
without eyes; leg I ending in several long hairs. Usually predaceous in 
habits, but sometimes parasitic. 
CHEYLETUS Latreille. 
Body longer than broad but never twice as long as broad; palpi 
swollen on the outer side near the base; hind legs provided with claws; 
papilla of palpus having at least one specialized comb-like bristle. 
Seldom parasitic, generally predaceous. 
One species. 
Cheyletus longipalpus Nn. sp. 
Pl Vi J. 
Light orange; legs and palpi lighter than the body; integument 
coarsely granular. 
Cephalothorax slightly larger than the abdomen and possessing four 
rows of large, pectinate, fan-shaped scales; two rows of five scales 
each near the median line and two lateral rows of four scales each. 
Total length of the beak almost equal to the length of the rest of the 
cephalothorax; beak with a base much swollen dorsally and possessing 
a pair of small, straight bristles near the tip on the dorsal surface and 
a similar pair situated laterally to these. Palpi long, being a third 
longer than the beak. First segment of palpus small, disc-like; second 
segment enormous, long, curved, about equal to the total length of the | 
