3.32 BULLETIN 07, UNITED STATES NATIONAL MUSEUM. 



Uahits. — Dodge about rocks that are awash at high tide and hide 

 in crannies when pursued. Also at home on drift timber in the 

 open sea, which accounts for the wide range of some of the species. 



Distribution. — All warm seas; extends into the Mediterranean. 



KEY TO THE AMEUICAN Sl'ECIES OF THE GLNCS PLAUDSIA. 



A*. Carapace tuberculate. Merus joints of legs unispifiose anteriorly. 

 B*. Tubercles of carapace well marked. Merus joints of legs with two fringes 

 of hair on upper (or posterior) surface. 



C\ Coxal joints of legs with a dentate lobe dcprcssa, p. 332. 



C*. Coxal joints of legs with an entim lobe dcpretfia tnhcreulata, p. 334. 



B'. Tubercles of carapace depressed, ill-defined. Merus joints of legs with 



only a po.sterior fringe of hair on upper surface immaculata, p. 335. 



A'. Carapace tomenlose, nearly smooth. Merus joints of legs raultispinose 

 anteriorly chahrus, p. .^3C. 



PLAGUSIA DEPRESSA (Fabricius). 



Plate 101. 



Cancer dcprcssus Fabkicius, Syst. Entora., 1775, p. 40G (type-locality, in 



inari vieditcrraneo ; type in Kiel Mus.).' 

 Cancer sqv.amosiis Herust, Natur. Krnbben u. Krebse, vf)l. 1, 1790, p. 260, 



pi. 20, fig. 113 (type-locality, Ostindicn; type in Berlin Mus.?).* 



Probably confused with P. depressa tuhcrculata. 

 Grapsus dcprcssus Bosc, Hist. Nat. Crust, vol. 1, an X [1S01-1S02], p. 203. 

 Plagusia dcpressus Say, Journ. Acad. Nat. Sci. Philadelphia, vol. 1, 1817, 



p. 100. 

 Playiisia sayi De Kay, Zool. New York. Crust., 1844, p. 16 (type-locality. 



Gulf stream; type not extant). 

 Plagusia squamosa Latkeiixe, Encyc. Meth., Hist. Nat., Entom., vol. 10, 



1825, p. 14.5. 

 PI'KjuHia gracilis Saussuke, M6m. Soc. Phys. Hist. Nat. GenGve, vol. 14. 



1858, p. 449 [33] (type-locality, Cuba; type in Geneva Mus.). 



Diagnosis. — Carapace tuberculate. Coxal joints of legs with « 

 dentate Icbe; merus joints with one spine on anterior margin. 



Description. — All the regions of the carapace are distinct, and the 

 surface is covered with flat pearly or squamiform tubercles which are 

 fringed anteriorly with small close-set bristles of uniform length. 

 On the front of the gastric region is a series of about six prominent 

 acute tubercles arranged in an arc concave forward. Antero-lat- 

 eral border armed with four teeth (including orbital angle), 

 which in the main decrease in size from before backward. Epistome 

 prominent beyond the anterior border of the carapace and cut usually 

 into five Icbes. 



Chelipeds of adult male massive and about as long as carai^ace, 

 in the female slender and about three-fourths as long as carapace. 



'The suppospd typp-speclmen 1:^ lal)0)c(l " Alphcun depre.isus F." No locality is given. 



= 1 searched for the type but did not Hnd it. Illlgendorf, In 1882 (SB. Ges. Naturf. 

 Frounde Herlln, l.'?82, p. 24), says that the type-specimen of Cancer squat'iosus has the 

 lobe at the base of the legs entire, but this Is not the case in llerbst's fig. U.S. pi. 20. 



