1'OKTUNIDAE. 61 



Callinectes alexandri, sp. nov. 



PI. 2, Fig. 1 ; PI. 9, Figs. 3, 3 a,. lb. 



Young male. Extreme width of carapace about 2§ x the median length. 

 Regions well marked, as well as the two areolae at the inner angle of l he 

 branchial region. Granules of dorsal surface squamiform and conspicuous; 

 most scattered on the anterior third, finest and most crowded on the pos- 

 terior third. The granules of the customary ridges (two gastric and one 

 branchial) are more beadlike. The median length of the intramedial region, 

 or that part of the gastric region situated behind the second ridge, is nearly 

 | its anterior width. 



Frontal teeth four, besides the orbital pair. Median pair tuberculiform, 

 not more than \ the area of the triangular, obtuse, outer pair. Inner orbital 

 tooth lobiform and a little less advanced than the median teeth. Superior 

 fissures of orbit well marked, but closed ; inner suborbital lobe subacute, not 

 very prominent. 



The outer orbital tooth, or the first tooth of the lateral series, is equi- 

 lateral or subacute. Teeth 2 to 7 inclusive are saw-teeth, that is, shorter 

 on the anterior than on the posterior margin ; the second, third, and fourth 

 are acute, the fourth, fifth, and sixth are acuminate and slightly concave on 

 the posterior margin. Eighth tooth curved forward, acuminate. The mid- 

 rib of the ninth projection, or the lateral spine, is quite transverse ; its length 

 is about \ of the carapace, exclusive of the lateral spines. 



The shape of the abdomen of the young male is probably not that of 

 the adult; the sixth segment tapers gradually to the distal end, the seventh 

 is equilateral. 



Chelipc-ds very finely rugose, the costae of wrist and hand prominent and 

 more closely granulate; three strong curved spines on the anterior margin 

 of the merus ; posterior margin unarmed. The outer spine of the carpus is 

 well developed, though much smaller than the inner. Of the two spines 

 of the palm, the proximal is curved, the distal is very slender. 



Dimensions: — Length of J, type, 14.8 mm.; entire width, 3-5.7 mm.; 

 length of lateral spine, 5 mm. 



Distribution : — 



Papeete, Tahiti; shore; Nov. 9, 1S99; 1 <?,juv., type (Cat. No. 32,854, 

 U. S. N. M.). 



Suva, Fijis; shore; Dec. 13, 1899; 1 ?, juv. 



