344 TUK KEV. T. R. H. STKlSUINCi ON 



MALACOSTRACA. 



BEACHYUEA. 



Tribe CYCLOMETOPA. 



Fam. A C A N T H O C Y C L I D -E. 



1852. CijcUnea Dana, U.S. Expl. Exp. vol. xiii. p. 294. 

 1886. Cyclinea Miers, Rep. Voy. ' Challenger,' vol. xvii. pt. 49, 

 p. 208. 



1898. Acanthocyclidie Rathbun, Pr. U.S. Mus. vol. xxi. p. 597. 



1899. Acanthocyd'mni Alcock, J. Asiat. Soc. Bengal, vol. Ixviii. 



pt. 2, p. 9(>. 

 Alcock acce^jts Dana's legion as a subfamily of the Cancvi(Ue, 

 with the (leiiuition, "Carapace subcircular : front ending in a 

 triiingular point. Epistome .short, .sunken, conn^letely concealed 

 by the external niaxillipeds which also comjjletely cover the buccal 

 oritice. Antenna! flagella absent." The second character niu.st 

 lie modified for the specimens referred to A. cdbcUrossis, as in them 

 the front is not triangular. 



Gen. AcANTHOOYCLus M. -Edwards &, Lucas. 



1844. Acanthocycli(s Milne-Edwards & Lucas, D'Orbigny's A"oy. 



Amor. Mcrid. vol. vi. pt. 1, p. 30. 

 1849. Acanthocyclas Nicolet, Gay's Hist. Chile, Zool. vol. iii. p. 176. 

 1898. Acanthocyclus Ilathbun, Pr. U.S. Mus. vol. xxi. p. 597 



(with further synonymy). 



ACANTHOCYCLUS ALUATKOSSIS Rathbun. 



1861. Acanthocydas yayi Strahl, Monats. Ak. Wiss. Berlin, July 



25, 1861 (1862), p. 713, pi. 

 1&77. „ ,, Targioni-Tozzetti, R. 1st. Stud, super. 



Firenze, vol. i.«, Crost. della Magenta, 

 p. 95, pi. 7. fig. 1, a-f. 

 1898. A. alhatrossis Rathbun, Pr. LT.S. Mus. vol. xxi. p. 599. 



Miss Rathbun distinguishes tliree species of the genus — the 

 original A. gayi M. -Edwards & Lucas, 1843, renamed A. villosiis 

 by Strahl in 1861, Strahl's A. gayi, for which pieoccu})ied name 

 A. albatrossis is substituted, and A. hassleri, discovered by 

 ])r. Faxon, but by his wish described and named by Miss Rathbun, 

 who remai-ks that " the general appearance of tlie three species 

 is much the same," but that the diflerences are constant. Of 

 these eleven are tabulated, and, granting in each case the con- 

 stancy of the combination, the specific distinction may be justified. 

 Taken se2)arately, many, even most if not all, of the diflerences 

 I'elied on, have a rather untrustworthy a])pearance. Thus the 

 front is entiie in f/ayi and hassleri, faintly bilobed in al/)((trossis ; 

 the dactyli of andadatory legs are long, little curved in the last, 

 sliort, much curved in the other two; both caraj)ace and legs are 

 very hairy in gayi, less hairy in both the others, which again have 

 the carapace tuberculate, whereas in gayi it is almost .smooth ; 

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