THE CANCROID CRABS OF AMERICA 135 



Lupa cribraria Milne Edwards, Hist. Nat. Crust., explanation of plates, p. 15, 



pi. 17, figs. 1-4. 

 Arenae^is cribrarius Dana, U. S. Expl. Exped., vol. 13, Crust., pt. 1, 1852, p. 290; 



atlas, 1855, pi. 18, figs. 2a, 26.— Rathbun, Bull. U. S. Fish Comm. for 1900, 



vol. 2, 1901, p. 50.— Sumner, Bull. Bur. Fisheries, vol. 31, pt. 2, 1911, p. 



672.— Hay and Shore, Bull. Bur. Fisheries, vol. 35, 1915-16 (1918), p. 434, 



pi. 34, fig. 3. 

 Neptunus cribrarius A. Milne Edwards, Arch. Mus. Hist. Nat. Paris, vol. 10, 



1861, p. 324; Crust. Reg. Mex., 1879, p. 211. 



Diagnosis. — Four frontal teeth. One spine at distal end of manns. 

 Outer and inner spines of wrist subequal. 



Description. — Carapace more than twice as wide as long, almost 

 smooth to the naked eye, but through the lens closely covered with 

 fine granulation. Front narrow, much less advanced than the outer 

 orbital angles and armed with four small teeth (between the orbital 

 teeth) the two median more prominent and more widely separated 

 from each other than from the outer ones, with which they are partly 

 coalesced; median sinus U-shaped, outer sinuses nearly rectangular. 

 Inner tooth of orbit bluntly triangular; superior border divided by 

 two wide incisions, the inner deeper than the outer, intermediate lobe 

 narrow, sub truncate; inferior border forming a broad sinus between 

 outer and inner tooth. Antero-lateral teeth wide, covered below 

 with a fringe of hair which screens the interspaces; teeth very 

 unequal, the first five narrower than the next three, the seventh 

 widest. Lateral horn strong, as long as the space occupied by the 

 last two teeth. Pterygostomian and antennal regions and epistome 

 covered with hair. 



Chelipeds short and stout. Three or four spines on anterior border 

 of merus; a short spine or tubercle, sometimes obsolete, on the pos- 

 terior border at the sinus and another at distal end a little above or in 

 front of the posterior border. Wrist with two short spines, one inside, 

 the other outside; two denticles on the outer distal margin; and one 

 or two on the dorsal surface terminating longitudinal carinae. Five 

 tuberculate longitudinal carinae on the manus, the upper-inner -one 

 terminating in a spine. Ambulatory legs wide. Swimming legs also 

 very wide, the merus arcuate and unarmed below. Sixth segment of 

 abdomen of male narrow; margins of last segment sinuous, extremity 

 very narrow. 



Color. — Grayish formed by a multitude of small white or light 

 yellow spots on a background of fawn or light brown. (Desbonne.) 

 Light vinaceous brown or olive brown thickly covered over the dorsal 

 surface with small, rounded, white spots; tips of walking legs yellow. 

 (Hay and Shore.) The spots on the dorsal surface of the chelipeds 

 are larger than those of the carapace. The color pattern persists in 

 alcoho] . 



