DESCRIPTION OF GENERA AND SPECIES. . 211 



strongly projecting sidewise, of about equal size, separated by about the diameter of SR ; 

 they are distant from MF by three times or more the area of the latter; of clypeus about 

 two diameters MF high, the margin touching the quad eminence. The front row is very 

 slightly recurved, almost aligned ; the rear row is slightly procurved, almost aligned. 



LEOS : 1, 4, 3, 2; in all specimens a uniform blackish brown ; freely provided with strong 

 spinelike bristles, but with no ordinary spines; palps colored and armed as legs; mandibles 

 arched at the base, conical, glossy, blackish brown. 



ABDOMEN : Considerably wider than long ; semicircular in front and behind ; the sides 

 somewhat square and truncate, caused by the presence on each of two blunted cones, of 

 which the posterior is somewhat larger; the dorsal field is yellow, but deeply marked with 

 black patches, which environ the dimples, and in front are merged into two bands. There 

 are twelve dimples in the front row and nine in the posterior. From the apex of the 

 dorsum project two short, black, conical spines ; the sides and apical wall are mottled 

 yellow and black, covered profusely with short hairs set in a circular cavity ; a row of 

 dimples encompasses the spinnerets, which are jet black and set at the apex of the conical 

 venter. The epigynum (Fig. 12a) is an obtusely triangular or semicircular flap, slightly pro- 

 longed at the apex into a short rounded scapus ; the atriolum is wide, and, looked at from 

 beneath, shows deep hollows on either side of the base of the scapus; color black, glossy, 

 except at the extreme tip, which is yellowish brown. 



DISTRIBUTION : Numerous specimens, young and old, of this species have been obtained 

 from California, particularly the southern part (Dr. Blaisdell, Mr. Orcutt), and from islands 

 off the coast (Mr. C. H. Townsend). 



No. 65. G-asteracantha preciosa, new species. Plate XIV, Fig. 7. 



1889. Gasteracantha predosa, MARX in lilt. . . Catalogue, p. 539. 



FEMALE: Total length, 6 mm.; cephalothorax, 2.5 mm. long, width at the face 2.3 mm.; 

 the abdomen 6 mm. long, 8 mm. across the middle. The description of Gasteracantha pal- 

 lida will apply to this spider in almost every detail except the general color. The ceph- 

 alothorax, mouth parts, and legs are extremely glossy, and blackish to blackish brown, 

 except upon the terminal joints of the legs. The dorsal field of the abdomen, instead of 

 being a pale yellow, as with G. pallida, is jet glossy black, mottled with large irregular 

 patches of bright yellow placed in front and along the margins, and near the middle part 

 of the margins present a striking appearance. The number of circular pits or dimples 

 around the margins is also greater than in G. pallida, numbering eleven on the base and 

 ten on the apical half of the dorsal circle. The spines projecting from the middle part are 

 yellow at the base, succeeded by a bright rosy red, the point being jet black, all covered 

 with circular rows of spines with roughened bases. There is a decided conical process on 

 coxa-II which is wanting in the example of G. pallida before me. The epigynum shows 

 simply a low atriolum, with a hard, glossy black, semicircular edge without a scapus. 



DISTRIBUTION: Mohave Desert, California. 



No. 66. Gasteracantha cancriformis (LINN^US). Plate XIV, Fig. 9. 



1767. Aranea cancriformis, LIXN.EUS . . Syst. Nat. Ed., xi., p. 1037. 



1837. Plectana cancriformis, WAI.CK. . . Ins. Apt., ii., p. 151. 



1837. Plectana elipsoides, WALCKENAER . Ins. Apt., ii., p. 155; ABBOT, Ga. Spid. 



1850. Epeira cancer, HENTZ J. B. S., vi., p. 23. Sp. U. 8., p. 126, xiv., 13. 



1889. Gasteracantha cancriformis,McCooK. Amer. Spid. and their Spinningwork, Vols. I, II. 



1889. Gasteracantha cancriformis, MARX. Catalogue, p. 539. 



FEMALE : Total length, 7 mm. ; width at the face, 3 mm. ; abdomen, 5 mm. long, 8 mm. 

 wide. 



The cephalothorax and caput are of the typical form, the color glossy black, with a 

 tint of brown. The sternum and mouth parts are typical, as are also the eyes. The legs 



