146 PROCEEDINGS OF THE ACADEMY OF [1880- 



are finely denticulate. Thumb smooth below its inner margin 



with several rows of granulations and a prominent tooth near the 



middle (J. et L.). 



Unknown (J. and L. ) Nicobars (Heller). 



20. Gelasimus signatus Hess. PI. x, f. 18. 



Oelasimus signatus Hess, Archiv fur Naturgeschichte, xxxi, p. 146, PI. 

 VI, f. 6 (1865). 



" Front between the eyes not so small as a G. variatns, cheliped 

 one and a half times the breadth of the body; arm, carpus and 

 hand bright red, fingers white. Arm below with two rows of 

 pearlj' tubercles, fingers with an elevation at the middle of the 

 inner border, distallj' arcuate and pointed " (Hess). 



Sydney, Australia (Hess). 



21. Gelasimus crassipes White. PI. x, f. 19. 



Oelasimus crassipes White, Cat. B. M. Crust., p. 36, sine descr. ; 

 Adams and White, Voyage Samarang Crustacea, p. 49 (1848). 



? 0. brevipes Edw., Ann. Sci. Nat., Ill, xviii, p. 146 (1852). 



" Carapace very much arched, suddenly narrowed behind, front 

 with a lobe without narrow stalk. Four hind pairs of legs thicker 

 and stronger than in the other species " (Ad. and White). 



Philippine Islands (White). 



There have been described three other species * belonging to 

 the narrow-fronted section, one of which has been made the type 

 of the genus AcanthopJax by Milne Edwards. A fourth species 

 from Bahia, Brazil, is in the collection of the Philadelphia 

 Academy-. So far as 1 am aware these are all females and are 

 represented by only a single specimen each, and as I am strongly 

 inclined to consider them the females of well-known forms I omit 

 descriptions of them. 



* Oelasimus insignis Smitli, Trans. Conn. Acad., ii, p. 126 (1870). 

 Acayithoplaxinsignis'Edw., Ann. Sci. Nat., Ill, xviii, p. 151, PI. IV, 

 f, 23 (1852) ; Archives des Museum, vii, p. 162, PI. II, f. 1 (1854).— 

 Chili (Edw.). 



Oelasimus ornatus Smith, Trans. Conn. Acad., ii, p. 125, PL II, f. 9, 

 PI. Iir, f. 5 (1870) ; Report Peabody Acad. Science, iii, p. 91 (1871).— 

 West Coast Nicaragua! McNiel (Peab. Acad.). 



Acanthoplax excellens Gerstiicker, Archiv fiir Naturgeschichte, xxii, 

 p. 138 < 1856). -No locality. 



