Figure 207. — Plagusia depressa (Fabricius). Animal in 

 dorsal view (after Rathbun, 1933). 



Chelipeds of adult male massive, approximately 

 as long as carapace, in female slender, three- 

 fourths as long as carapace; chelipeds and legs 

 rugose dorsally; merus with three small spines 

 above at distal end; carpus with inner angle 

 densely dentiform; palm and dactyl with tuber- 

 cles arranged in longitudinal ribs, outer surface 

 smooth. Walking legs strong, increasing in size 

 from first to third, fourth shorter than second; 

 second and third legs with a dentate crest above 

 on coxae; meri with subterminal spine on anterior 

 border; distal three articles with a dense strip of 

 long hair; dactyls with two rows of strong spines 

 on concave side. 



Measurements. — Carapace : large female, length, 

 45 mm. ; width, 49 mm. 



Color. — Light reddish, dotted with blood red, 

 tubercles bordered with blackish cilia with ex- 

 tremity gray; blood-red spots on legs; underside 

 of body yellowish (Latreille in Rathbun, 1918b). 



Habitat. — This species is found among rocks, 

 on jetties, in tide pools, and is thought to be trans- 

 ported on ships' hulls. 



Type locality.- — "In man mediterraneo.'''' 



Known range. — Beaufort, N.C. through West 

 Indies to Pernambuco, Brazil; Bermuda; Azores; 

 Madeira; West Africa, from Senegal to Gold 

 Coast. 



Genus Percnon Gistl, 1848 



Rathbun, 1918b, p. 337. — Hemming, 1958b, p. 35. 



Percnon gibbesi (Milne Edwards). Spray crab 



ocarpus gibtesi Milne Edwards, 1858, pp. HG and ISO. 

 Percnon gibbesi: Rathbun, 1918b, p, 337.— Schmltt, 1939, p. 24. 



tuition characters. — Carapace thin, disc- 

 like, longer than wide, covered with small short 



bristles except for bare raised patches; dorsal sur- 

 face with a few low tubercles. Front deeply cut 

 by antennular furrows; portion between anten- 

 nules narrow and extended in form of a rostrum, 

 armed with two erect spines on each side distally 

 and a row of inconspicuous spinules just within 

 and parallel to each margin proximally. Eyes 

 large, reniform. Inner margin of orbit bearing 

 three spines, two distal spines prominent; middle 

 of upper orbital border more or less serrate. An- 

 terolateral border of carapace with four acute 

 spines counting large spine on outer orbital angle ; 

 second spine in series with its lateral margin 

 shorter than that of third spine. 



Chelipeds varying in size with age and sex, 

 small in females but large and unequal in adult 

 males; merus and carpus armed with spines; palm 

 nearly smooth, oval, and somewhat compressed, 

 proximal upper surface with an ill-defined groove 

 extending one-third length of upper margin, 

 groove filled with pubescence; fingers short, blunt, 

 with tips concave on opposed surfaces. Meral arti- 

 cle of each walking leg with large uniform spines 

 on anterior margin, upper surface covered with 

 short bristles similar to carapace ; posterior mar- 

 gin ending in a distal spine; merus of first two 

 legs with a second row of spinules parallel with 

 anterior border, row indistinct on third merus 

 and absent on fourth. 



Measurements. — Carapace: male, length, 30 

 mm., width, 28 mm.; female, length, 33 mm., 

 width, 34 mm. (Garth, 1946). 



Color. — Carapace and meral articles of walk- 

 ing legs brown or mottled above ; usually a median 

 longitudinal stripe of white or pale blue; legs 

 banded with reddish, brown, and light pink dis- 

 tally; eyestalks and chelae orange; ventral side 

 of body pale blue with legs pale pink (Garth, 

 1946; Verrill, 1908). 



Habitat. — The usual habitat for this species is 

 the underside of rocks at the low-tide level (Ver- 

 rill, 1908), or in the surf at knee to hip depth, 

 where it is extremely difficult to capture because 

 of its propensity for rapidly keeping to the under- 

 side of turned objects (Garth, 1946). 



Type locality. — Antilles. 



Known range.— Fort Macon, N.C; southern 



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