ACHELOUS AFFINIS. 23 
ACHELOUS Dez Haay. 
Siebold’s Fauna Japonica, Crustacea, p. 8, 1833. 
Achelous spinimanus (Latr.). 
Portunus spinimanus Later. Nouv. Dict. d’Hist. Nat., 2e éd., XXVIII. 47, 1819. 
Portunus (Achelous) spinimanus De Haan, Fauna Japonica, Crustacea, p. 8, 1833. 
Station 3368. 66 fathoms. 2 males. 
These specimens differ from the typical form in havirg a shorter arm and 
hand, a longer spine on the inner side of the carpus; in having a short spine 
at the distal end of the superior border of the propodus and two small spines 
at the distal end of the merus of the last pair of legs. Of these two spines 
the larger is on the posterior lateral angle of the segment, the smaller one 
just above it. The carpal spine reaches half way to the extremity of the 
spine on the upper margin of the propodus when the hand is flexed. The 
length of the carapace is 44.5 mm.; breadth, 69.5 mm.; length of merus, 
33 mm.; length of chela, 47 mm.; breadth, 15 mm. ; length of dactylus, 25 
mm.; length of carpal spine, measured from the anterior border of the 
carpus, 10.5 mm. 
If these differences prove to be constant in specimens from this region 
the form may be called Achelous brevimanus. 
Achelous spinimanus inhabits the Atlantic coast of America from Cape 
Hatteras to Rio de Janeiro, Brazil. It has also been recorded from the coast 
of Chile. 
Achelous affinis Fax. 
Plate 1V., Fig. 1, 1°, 2. 
Bull. Mus. Comp. Zodl., XXIV. 155, 1893. 
Carapace moderately convex both longitudinally and transversely, the 
frontal region depressed and horizontal; surface rugose, granular, and 
pubescent. Front not prominent, composed of four blunt teeth, not 
counting the internal angle of the orbit; the two teeth near the median 
line are equilaterally triangular, separated from one another by a tri- 
angular notch; the next teeth on the outer side are separated from 
those within by a shallow sinus, and fall off abruptly on the outer side 
into the deep notch which separates the front from the inner orbital angle. 
The two middle teeth of the front are a trifle longer than the lateral teeth. 
