OF CONCHOLOGY. 145 



(A. sericea, S. and A.) This genus was properly characterized, 

 and is still in use. It has fifteen years' precedence over Argiope, 

 Desl., which necessarily becomes a synonym of the next regu- 

 larly proposed generic name applied to this group. This is 

 3Iegat}tyris of D'Orbigny, 1847, which must therefore be 

 adopted. For information in regard to Savigny's genus, see 

 Thorell, Ann. and Mag. Nat. Hist. 1868, p. 190. 



Fig. 23. 



Fig. 23. Megatltyris dfcollata, i, showing the apophyses. 



Type. Megatliyrls decoUata, Chemn., sp. fig. 22, 23. 

 Anomia decoUata^ Chemn., Con. Cab. viii, p. 96, pi. 78, fig. 



705. 



This is Anomia detru7icata, Gmel., + Terehratula deeollata, 

 Desh., + T. aperta, Blainv., + T. dimidiata, Scacchi, + T. car- 

 dita, Risso, + T. ui'na-antiqua, Risso, + Argiope deeollata of 

 Dav., Rve., and most modern authors. 



As Chemnitz was not a binomial writer, it is probable that 

 his specific name ought to give place to that of Graelin. 



Hab. Mediterranean, living; fossil in the miocene of Gib- 

 raltar and pliocene of Calabria. 



Subgenus Cistella, Gray. 



Cistella, Gray, B. M. Cat. Jan. 1853, p. 114. H. and A. 



Adams, Gen. Rec. Moll, ii, p. 581 (not Oistelia, GeofFr. 



and Fabr. Coleop.) 

 Zellania, Moore, Proc. Somerset Archgeol. and Nat. Hist. Soc. 



1854. Dav., Mem. Lin. Soc. Normandie 1856, p. 141, 



pi. vii (type, Z. Davidsoni, Moore, figs. 43, 44). Chenu, 



Man. de Conchyl. ii, p. 210. 



Shell with a single median submarginal septum and bilobed 

 loop. Surface smooth, or radiately ribbed. Brachia inter- 

 rupted by the septum. 



