NO. 2 WALTON : THE GENUS PYLOPAGURUS 153 



Precervical portion of carapace about as broad as long, transversely 

 convex, glabrous; median projection broadly triangular, apex produced 

 slightly into a more acute point; lateral projections of cardiac region 

 distinctly marked off as a pentagonal plate. 



Eyestalks stout, terete, constricted in middle, cornea dilated; oph- 

 thalmic scales bluntly triangular, longitudinally convex, with prominent, 

 acute, subterminal spine. 



Antennal acicle slender, outward-curving, pointed, slightly setose, 

 and approximating length of eyes; peduncles when extended exceeding 

 eyes by over one half length of slightly compressed terminal article; 

 flagella slender, slightly setose. 



Antennular peduncles when extended exceeding eyes by full length of 

 long slender terminal article ; inferior flagellum slender, evenly tapering, 

 about two thirds length of superior flagellum. 



Ambulatory legs wide, compressed, slightly longer on right side; 

 merus much compressed, smooth except for slight scales and setae on 

 superior and inferior margins; carpus rounded laterally, crested with 

 small sharp spines ; propodus of second pair sometimes similar but often 

 with spines reduced to mere scales; dactyls spinulose, with only sparse 

 setae. 



Fourth pair of thoracic legs subchelate, minute dactyl not bearing 

 rasp as does pollex and small distal portion of propodus; fifth pair 

 minutely chelate, with tuft of very long setae on distal end of laterally 

 swollen propodus. 



Membranous abdomen as long as carapace, membranous terga not in 

 contact, caudal shield calcified, suture flexible; anterior tergum trans- 

 versely and longitudinally convex, smooth, posterolateral corners pro- 

 duced slightly; posterior tergum similar in shape, slightly smaller with 

 few tufted setae on lateral and terminal borders. 



Telson symmetrical, fringed laterally by setae, posterolateral corners 

 with prominent, flat, downward curving tooth, entire terminal margin 

 between teeth occupied by denticulations of varying size ; uropods larger 

 on left side, anterior blade with rasp over most of outer surface, posterior 

 blade much reduced, completely covered by rasp on outer surface. 



Distribution: Arena Bank and Santa Inez Bay in the Gulf of 

 California (Glassell) ; near Espiritu Santo Island, Gulf of California 

 (Benedict). 



Specimens in the Hancock collections are from Ensenada de San 

 Francisco, Sonora, San Pedro Nolasco Island, Tiburon Island, Isla 



