GONEPLACIDAE. 



This family has until recent years been generally assigned to the Ocypodidae, to which 

 view the elongate eye-stalks of Goncplax at first sight afford a great probability. H. Milne- 

 Edwards in 1852 already divided his "tribu principale" Ocypodpiae into two "ageles": Ocypo- 

 diaceae and Gonoplaceac, the latter again was split up into '^ Gonoplaccs vigils' (including mostly 

 genera, that are now known to constitute the subfamily Macrophthalminae) and " Gonoplaces 

 canceroides\ with the genera Gonoplax, Oinmatocarcinus and Prionoplax. Besides, two genera, 

 PseudorJiombila and Care ifiop lax" ar.e, under the name CarcinoplacinaL\ designated as "tribu 

 satellite des Ocypodinac' '). 



This classification, with slight alterations, has a long time been maintained and the group 

 was, shortly after the publication of Milne-Edwards' paper, greatly increased by Stimpson "), who, 

 besides adding some new genera to the Carcinoplacidae, established a new family, Rhizopidae, 

 for the reception of several genera, and included both families in his "Ocypodoidea". 



MiERS ^) in 1886 divided the Ocypodidae into two subfamilies: Carcinoplacinac and 

 Ocypodinae, one of the subgroups of the latter being the Gonoplacinac. Both Carcinoplaci7iae 

 and Gonoplacinac were raised to the rank of families by Ortmann *) in 1 894 and united in a 

 group Carcinoplacini, that is definitely removed from the Ocypodidae, which are included in 

 another subgroup: Grapsini. This view, however, is far from having been accepted by sub- 

 sequent authors") who kept to the older classification, though Alcock '^) in 1900 definitely 

 established Ortmann's view, and, by adding to our family the Hexapodinac, still enlarged it. 

 In this paper Alcock's classification is followed. 



Already by their habits the present family differs widely from the Ocypodidae: none of 

 the species frequents the beach and none is living in fresh or brackish water; on the contrary 

 all the species are strictly marine, showing a preference to deeper layers and some genera 

 inhabit exclusively the deep sea. A great many of the species is very small and among these 



1) Ann. .Sc. Nat. (3), t. 18, 1852, p. 140—164. 



2) Proc. Ac. Nat. Se. Philadelphia, 1858, p. 93 — 96. 



3) Rep. "Challenger", Brachyuva, 1886, p. 222, 236—237. 



4) Zool. Jahrb., Syst., Bd 7, 1894, p. 683—685. 



5) Even in 1906 Miss Rathbun (Bull. U.S. Fish Comm. for 1903, v. 23, prt 3, p. S34— S35) persists in classing some genera 

 of the present family with the Ocypodidae. 



6) Journ. .As. .Soc. Bengal, v. 69, prt 2, 1900, p. 2S6— 287. 



