2l8 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3 d Ser. 



their diameter from each other, distinctly farther from the rather smaller 

 P. S. E.; A. M. E. fully one-half their diameter apart and closer to the equal 

 A. S. E. ; sternum rather oval, tapering and pointed behind. Legs moderate; 

 no spine under tibia; I, one under middle of tibiae II, two under base of met- 

 atarsi I and II; the posterior pairs with more spines, but none above on the 

 tibiae. Abdomen subcylindrical, hardly depressed, nearly twice as long as 

 broad. The epigynum shows a cavity somewhat triangular, with hardly 

 rounded corners, and with a tooth on the superior side, divided by a septum, 

 broadest near base, then gradually tapering toward tip, where it is somewhat 

 enlarged. 



Several examples from Orizaba, and Mt. Orizaba, Jan. 

 A small specimen from Mexico City shows the epigynum 

 rather broader, but of the same general character. 



41. Prosthesima gentilis, sp. nov. 



Plate XIII, Fig. 17. 



Length 3.3 mm. Cephalothorax, mandibles, sternum, and legs dull yel- 

 lowish; abdomen gray, mostly clothed with black hair, more prominent at 

 the base of abdomen. Cephalothorax low, much narrowed in front, dorsal 

 groove short; posterior eye-row straight; P. M. E. round, less than one- 

 half their diameter apart, distinctly farther from the nearly equal P. S. E.; 

 A. M. E. barely smaller, close together, not farther from the nearly equal 

 A. S. E; sternum once and a fourth longer than broad, sides rounded. Ab- 

 domen depressed, truncate at base. Legs short, apparently no spines under 

 tibia; I and II, quite a number below and on sides of posterior pairs. The 

 epigynum shows an angulated area longer than broad, narrowed in front, 

 and divided by a dark line; behind are two dark oval bodies. 



One specimen from La Chuparosa. 



42. Prosthesima fidelis, sp. nov. 



Plate XIII, Fig. 19. 



Length 3.6 mm. Cephalothorax, mandibles, sternum, and legs dull yel- 

 lowish; anterior patellae and tibiae darker above; abdomen dark gray above, 

 lighter beneath, clothed with black hair rather more thickly than in P. gen- 

 tilis. Cephalothorax low, quite slender, dorsal groove short; posterior eye- 

 row straight, about as long as the anterior row; P. M. E. round, close to- 

 gether, a little farther from the equal P. S. E. ; A. M. E. close together and 

 as close to the equal A. S. E. ; sternum oval, rather broader than in P. gen- 

 tilis. Abdomen depressed, truncate at base, broadly rounded behind. Legs 

 short, no spines below anterior tibia;, a few on the metatarsus; posterior 

 pairs numerously spined; weak scopulas on anterior tarsi. The epigynum 

 shows a nearly square area bounded, except behind, by a black ridge and 

 divided by two median lines; behind on each side is a dark opening on the 

 margin of an obscure mark. 



