60 BULLETIN 168, UNITED STATES NATIONAL MUSEUM 



and anal segments ankylosed, without a suture. Tibiotarsus with a 

 distal subsegment. Hind claws the largest. Unguis (pi. 23, fig. 250) 

 stout, without lateral teeth, with inner margin unidentate two-thirds 

 from the base. Unguiculus lanceolate, acute, untoothed, extending 

 half as far as the unguis on the hind feet, two-fifths as far on the other 

 feet. Knobbed tenent hairs absent. Furcula attached between the 

 fourth and fifth abdominal segments, relatively short, extending to 

 the middle of the second abdominal segment. Manubrium with 

 several dorsal setae, and without ventral setae excepting a subapical 

 pair. Dens one-third longer than manubrium, slender, gradually 

 tapering, with many fine dorsal crenulations: absent basally and 

 ending distally at a distance from the mucro equal to twice the length 

 of the latter. Dentes with several long proximal dorsal setae and 

 many stiff ventral setae. Mucro (pi. 23, fig. 251) small but relatively 

 stout, three-fifths as long as hind unguis, or a little longer than hind 

 unguiculus, subequally bidentate; apical tooth curving, attaining 

 almost the height of the second tooth, which is erect. Kami of 

 tenaculum quadridentate; corpus with one stout stiff ventral seta. 

 General clothing (pi. 23, fig. 252) of dense, short, stiff, simple setae; 

 erect sensory setae short and simple. Integument smooth. Maxi- 

 mum length, 1.5 mm. 



Remarks. — In 85 percent of the specimens there are two eye patches 

 on each side of the head; in 15 percent the two patches are confluent, 

 sometimes broadly, but usually by means of a narrow connection. 



My redescription of P. aquae has been made from a large number of 

 specimens given to me by the author of the species. 



Distribution. — This species is known as yet only from California, 

 where it was found "in great abundance on pools of water in a newly 

 plowed field after a hard rain." It was taken also under rocks. 

 California: Claremont-Laguna region, G. A. Bacon. Indian HiU, February, 

 A. K. Payne. 



PROISOTOMA (PROISOTOMA) DECEMOCULATA, new species 



Plate 23, Figures 253-255 



Description. — White to the naked eye. Slightly pigmented with 

 minute dark points and patches. Antennae slightly pigmented; legs 

 white, pigmented basally; manubrium pigmented, dentes white. 

 Eyes (pi. 23, fig. 253) five on each side, equal. The two anterior eyes 

 occupy a single elliptical spot of pigment; the three posterior eyes 

 are pigmented separately, each being on a round black spot. Post- 

 antennal organ (pi. 23, fig. 253) subelliptical, about three times as 

 long as the diameter of an eye, with a trace of a constriction near 

 the middle of the anterior margin. Antennae subequal to head in 

 length, with segments as 14:18:20:37. Fourth abdominal segment 

 longer than the third (as 15:13). Unguis (pi. 23, fig. 254) simple, 

 curving, without lateral or inner teeth. Unguiculus lanceolate, ex- 



