268 REV. T. R. R. STEBBING ON STALK-EYED CRUSTACEA MALACOSTRACA 



Genus Gecarcinus, Leach. 

 1814. Gecarcinus, Leach, Edinb. Encycl., vol. xvii. p. 430 (see also pp. 391, 435). 

 1825. ,, Desmarest, Consid. gen. Crust., p. 113. 



1835. Ocypoda, Freminville, Ann. Sci. Nat., ser. 2, vol. iii. p. 224. 

 1836 (?) Gecarcinus, Guerin, Icon. Regne Anim., "Crust." pi. v. 

 1837. „ Milne-Edwards, Hist. Nat. Crust., vol. ii. p. 25. 



1858. ,, Saussure, Crust. Mexi que- Antilles, p. 23. 



1886. Geocarcinus, Miers, Rep. Voy. " Challenger," vol. xvii. part xlix. p. 217. 



1893. Gecarcinus, Stebbing, History of Crustacea, Internat. Sci. Ser., vol. lxxiv. p. 79. 



1894. „ Ortinann, Zool. Jahrb., vol. vii. pp. 732, 740. 



1895. ,, Bouvier, Bull. Nat. Hist. Mus. Paris, vol. i. p. 8. 

 1897. ,, Rathbun, Ann. Inst. Jamaica, vol. i. No. 1, p. 24. 

 1901. „ Rathbun, Bull. U.S. Fish. Comm. for 1900, vol. ii. p. 14. 

 1910. „ Rathbun, Pr. U.S. Mus., vol. xxxviii. p. 812. 



In this genus of land crabs the small terminal joints of the endopod of the third 

 maxillipeds, sometimes called the palp, are completely concealed in a ventral view by 

 the large fourth joint, and the angle which this joint forms with the third leaves 

 open a lozenge-shaped gap between the two members of this pair of maxillipeds. 



In 1837 Milne-Edwards distinguished three species based respectively on the 

 Cancel' ruricola of Linnaeus and many other authors, the Ocypoda lateralis of 

 Freminville, and an Australian form which he named G. lagostoma. His new 

 species agreed with G. ruricola in having the fingers of the ambulatory limbs armed 

 with six rows of spine-teeth instead of the four which characterise G. lateralis. Its 

 carapace was said to be smaller than that of G. ruricola, which, however, is not the 

 case. The colour is not mentioned, so that the only point of distinction was left 

 dependent on the third maxillipeds, in which the merus or fourth joint is described 

 as having a deep fissure on its internal edge above the following joint, while in 

 G. ruricola there is no notable fissure. 



Gecarcinus lagostoma, Milne-Edwards. 



1837. Gecarcinus lagostoma, Milne-Edwards, Hist. Nat. Crust., vol. ii. p. 27. 



1886. Geocarcinus lagostoma, Miers, Rep. Voy. "Challenger," vol. xvii. part xlix. p. 218, pi. xviii. 



figs. 2, 2a-c. 

 1893. „ „ Benedict, Pr. U.S. Mus., vol xvi. p. 537. 



1893. Gecarcinus lagostoma, Ortmann, Decap. und Schizop. Plankton-Exp., p. 58. 



1894. „ ,, Ortmann, Zool. Jahrb., vol. vii. p. 740. 

 1900. „ „ Rathbun, Pr. U.S. Mus., vol. xxii. p. 277. 



Two large female specimens of this species from Ascension Island were given to 

 the Scotia collection by Mr Chalmers. They fully equal in size the specimen from 

 the Challenger Expedition figured by Miers, and surpass it in the massiveness of the 

 chelipeds. Mr Chalmers also presented a much smaller female, matching in size 

 and colouring a male specimen taken by the naturalists of the Scotia on June 1, 

 1904. These small specimens, after nearly nine years in preservative liquid, still 

 have the larger part of the carapace dark purple with six light spots, one outside 

 each eyelobe, the other two pairs at spaces converging towards the median groove. 



