74 Trans. Acad. Sct. of St. Louts. 
stigmatic organ with long, narrow pedicel and large clavate head, the 
anterior margin of which is strongly pectinate. 
Abdomen almost twice as long as broad. Pteromorphe small, trun- 
cate anteriorly and not projecting beyond the anterior margin of the 
abdomen, attached to the anterior half of the same. Genital covers 
smaller than the anal covers and situated a little over their length in 
front of the latter. Abdomen hairless. } 
Tarsus and tibia of leg I subequal; tarsus well clothed with hairs; 
tibia sparsely clothed with hairs but possessing a large tactile hair aris- 
ing from a small tubercle at the distal, lateral aspect. Claws of tarsus 
monodactyle. 
Length, 0.44 mm.; breadth, 0.26 mm. 
In trash. Collected by C. R. Crosby at Columbia, Mo. 
TYROGLYPHIDAE. 
Body soft; without trachee; legs supported by rod-like epimera; palpi 
of three segments; eyes wanting; legs arranged into two groups and 
ending in claws, tarsi of legs I and II with a specialized clavate hair. 
Young frequently passing through a migratory stage, known as the 
hypopial stage in which they attach themselves to insects by means of 
a number of disc-like suckers on the ventral surface of the body. 
TYROGLYPHUS Latreille. 
Mandibles chelate; cephalothorax and abdomen divided by a suture; 
cephalothorax with four large posterior bristles; integument not granu- 
lar; ventral apertures small; male with anal suckers; tarsi rather slen- 
der, provided with distinct claws, and in some species with spines. 
One species. 
Tyroglyphus magnisetosus Nn. Sp. 
Pi XT. f. 88. 
Brownish grey; legs lighter than the body. 
Cephalothorax broad, three-fourths as long as the abdomen. Anterior 
pair of bristles slightly curved, almost one-half as long as the posterior 
bristles; posterior bristles subequal, fully as long as the abdomen. 
Abdomen oval, two-thirds as broad as long and bearing about twenty 
large, long, almost straight, simple bristles, the longest of which are 
fully as long as the entire body. The bristles of the abdomen are dis- 
tributed as follows—a transverse row of six bristles situated near the 
anterior margin, the two outer of these bristles being much smalier than 
the rest; a transverse row of four large, subequal bristles situated near 
the middle of the body; a group of eight bristles situated at the posterior 
end of the abdomen. 
Legs moderate; anterior pair about as long as the abdomen. Tarsus 
of leg I twice as long as the tibia; sense hair situated its length from 
the posterior margin of the tarsus; tarsus without stout spines, but pos- 
