4 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



corneous strips unite. Legs short, I not as long as width of body, with 

 a weak caroncle at tip; leg II enlarged, armed as in the figure, four pro- 

 cesses from femur, two on basal part, and two near tip, one near tip of 

 tibia, and the tarsus with two stout subterminal spines; legs III and IV 

 simple, quite long, with many almost spine-like bristles; the caroncle of 

 leg IV about one-half as long as tarsus IV. On the venter is seen a 

 broad sternal plate, with a bristle in each corner and at middle of sides; 

 other plates indistinct, but bristles at bases of coxae and others on venter, 

 and a fine hair each side of anus. -The spiracle has a long peritreme 

 reaching nearly to front of body. 



Length, 1.3 mm. 



Many specimens from Los Palmos, 3,500 feet, Santa Rosa 

 Mountains, California, May 27, taken by Mr. F. Grinnell, 

 from Peroguathus. The mites use their enlarged second pair 

 of legs to hold the hair of the host. 



Gamasus calcarator, new species. 



Body of male once and a half longer than broad, with a broad hood, 

 in front covering mouthparts; dorsal shield divided in the middle, on 

 sides, and behind with many long, fine hairs. Leg I very slender; leg 

 II heavy, the femur rounded above and on outer side very prominent, 

 below with a long, curved, toothed process, next joint also with process be- 

 low, tarsus like a large claw; hind legs slender, hairy, a spine above on 

 femur, and two below near middle of tibia?, and two on outer side of 

 metatarsi. Female narrowed in front, but the mouthparts visible. 

 There is a large, broad ventral plate, including the anus and reaching 

 forward to coxae IV. The color is pale yellowish, leg I paler than the 

 others. 



Taken from nest of field mouse at Falls Church, Virginia, 

 in November. 



Gamasus partitus, new species. 



Pale yellowish. Body nearly twice as long as broad, broadest behind 

 the middle, in front with a shoulder-like part, the dorsal shield nearly 

 divided beyond the middle, the posterior part truncate behind; a pair of 

 large bristles in middle near the front margin, a still larger humeral 

 bristle and one each side on posterior part of the anterior shield; pos- 

 terior shield with a number of small, fine hairs, mostly in rows, and some 

 hairs beyond the shield, a small clavate hair each side near outer 

 hind corner of shield. Legs very long and bristly, a bristle at tip of 

 hind tibia is twice the length of that joint, a few stouter spines, one 

 near middle of the hind tarsus below. A few hairs each side on the 

 sternal plate, and some behind near tip of the body. 



Length, 0.8 mm. 



Falls Church, Virginia. 



