GEAPSIDAE. 33 



Abdomen of & rather narrow; terminal segment much longer than 

 wide. 



Dimensions: — Length of carapace 8.3 mm.; width 9.1 mm.; fronto- 

 orbital width 7.5 mm. ; front 4.4 mm. 



Sesarma (Sesarma) rotundatum Hess. 



Sesarma rotundata Iless, Arch. f. Naturg., 1865, 31, 1, 149, pi. 6, fig. 9. Miers, Troc. 



Zool. Soc. London, 1877, 133, 136. De Man, Zool. Jahrb., Syst., 1887, 2, 654, 682. 

 Sesarma deutifrons A. Milne Edwards, Nouv. Arch. Mus. Hist. Nat. Paris, 1869, 5, 31. 



De Man, Zool. Jahrb., Syst., 1887, 2, 651; Jahrb. Hamburg. Wiss. Anst., 1896, 13, 



110, pi. 3, figs. 6 and 7. 

 Sesarma gardineri Borradaile, Proc. Zool. Soc. London, 1900, 593, pi. 42, fig. 8. 

 Sesarma (Sesarma) gardineri Nobili, Ann. Mus. Nat. Hungarici, 1905, 3, 497. 

 Sarmatium faxoni Ivathbuu, Bull. U. S. Fish Comm. for 1903 (1906), part 3, 841, pi. 7, 



fig. 1. 



Aruo Atoll, Marshall Group; Jan. 27, 1900; 1 S. 



Distribution: — Oahu and Marshall Islands (Rathbun) ; Duke of York 

 Island (Miers) ; Upolu (A. M. Edwards) ; Funafuti and Rotuma (Borradaile) ; 

 Nairai, Fijis (Miers) ; Seleo, Berlinhafen, New Guinea (Nobili) ; Sydney 

 (Hess). 



I think that Nobili is correct in his surmise that S. gardineri Borradaile is 

 the same as 8. rotundatum Hess. This is also the species that I mistakenly 

 placed in Sarmatium, S.faxoni (loc. cit.). In the two specimens before me, 

 <? and ?, the anterior § of the branchial region is inflated. The 3 (Aruo) 

 has a soft shell, the lower edge of its front is visible in a dorsal view ; in 

 the 9 (Oahu) this edge is invisible in a dorsal view. In the £ the posterior 

 margin of the orbit slopes distinctly outward and backward ; in the ? almost 

 imperceptibly so. 



Neither of these specimens agrees in detail with the type of S. deuiifrons 

 A.M.Edw. or of S. rotundatum Hess as figured by de Man {loc. cit.), or with 

 the figure of S. gardineri Borradaile, but the differences may be attributed 

 to individual variation. 



Sesarma (Sesarma) trapezoideum (Milne Edwards). 



Sesarma trapezoidea Milne Edwards, Hist. Nat. Crust., 1837, 2, 74. De Man, Zool. 

 Jahrb., Syst., 1887, 2, 654 ; 1889, 4, 426, pi. 9, fig. 7. 



Fatana River, Tahiti; Nov. 7, 1899; 1 $. 



3 



