454 ARACHNID A 



have 3 pairs of legs and are parasitic on insects, spiders, etc., Trombidium 

 being very common on house flies in the autumn, certain species, espe- 

 cially in the southern states, attacking man: about 4 American geneia 

 Avith 30 species, none of which are parasitic as adults. 



Trombidium Fabricius. Mandibles chelate; eyes stalked: about 12 

 American species, which are found on plants and on the ground, and 

 walk slowly. 



T. sericeum Say. Body broadest in front, densely covered with short 

 silken hair; eyes 2 and stalked and white: the commonest species in the 



<^^ ^ eastern states, living on trees and on the ground. 



.<3^Mft8/^3^ '^' locustarum Riley 



'^'"'yij^!^!^^^ ^ (Fig. 713). Bodyelon- 



( ] ^W^Ui^*^^^ g'^te, red, tapering be- 



A """^- 'ki. \\ f^^ ,5J«*A^^-vv bind; male with a 



v/n" IbH \h l\ /.r f^r^ V_» sunken elliptical area 



^ \^y } ^^ » 3\ /^ above ; 4 to 5 mm. long : 



A B « ^'c ^^ ground, young on 



Fig. 713 — Trombidium locustamm (Banks). A, ventral grasshoppers, 

 aspect of male ; B, eye-stalks ; C, a larva. 



Family 14. RHYNCHOLOPHIDAE. 



Like the Tromhidiidae, but with piercing mandibles and sessile eyes; 

 a mid-dorsal line or furrow on cephalothorax : 3 American genera, the 

 individuals of which walk rapidly. 



Rhyncholophus Duges. Mandibles slender, needle-like, and retrac- 

 tile; eyes 4 and sessile; legs long: 15 American species, which feed on 

 small insects, such as aphids and scales, and run rapidly. 



R. simplex Banks. Body red, 2.2 mm. long, with some erect bristles 

 on the body and among them many fine hairs; all legs long, hind pair 

 longer than the body : on dry ground. 



R. maculatus Banks (Fig. 714). Body with red spine-like hairs, 

 leaving several smooth white patches; legs short, hind pair no longer 

 than body; length 1.5 mm.: on ground and plants. 



Family 15. TETRANYCHIDAE.* 



Red spiders. Body oval, with a few bristles arranged in about 4 

 rows, and with a transverse suture between the second and third pairs of 

 legs, and red in color; 2 or 4 eyes, without stalks; pedipalps 4-jointed, 

 the penultimate joint usually with a strong claw; mandibles with their 

 basal portions fused and tips long and flexible, and fitted for piercing 



* See "The Red Spiders of the United States," by N. Banks, Bull. No. 8, Tech. 

 Ser., Div, Ent., U. S. Dept. Agr., 1900. 



