236 Mr. E. A. Smith o)i a new Species o/Mylitta. 



(c) Description of a new Species of Mtlitta. 



Mylitta auriculata^ sp. n. (PI. XIII. A. figs. A, B, C) 



Testa subcirciilaris, asqiiilateralis, superno utriuque umbones auricu- 

 lata, auriculis teuiiibiis, exciirvatis, alba, mcdiocriter convexa ; 

 valva3 crassa3, umbones versus sublaeves, deinde usque ad mar- 

 ginem radiatim fortiter costatse, costis subacutis, promineiitibus, 

 inter costas coneentrice rugose striata), vol teuuissime lamellatfe : 

 umbones parvi, acuti, antrorsum curvati ; dens cardinalis unions 

 valvoe dextra} parvus, conicus, laterales duo utrin(iuo sed propo 

 umbonem validi, divergentes; dens cardinalis valvse sinistra) 

 bifurcatus, lateralis unicus utrinque prominens, crassus ; fossa 

 ligament! profunda, mediana, subtriangularis, pone dentera car- 

 dinalem sita : pagina interna radiatim sulcata, ad marginem valde 

 crenulata, ad extremitates costarum broviter incisa ; cicatrices 

 parva), subrotundoD, et liuea pallii simplex, 



Longit. 8 millim., alt. 6|, diam. 3j. 



Ilah. Tasmania. 



In solidity, colourj and dentition tliis very remarkable shell 

 agrees exactly with the type of Mylitta^ but differs from it in 

 having the superficial costaj arranged in a radiating instead 

 of a divaricating manner. This difference, as in the case of 

 Pythina with regard to Kellia^ I regard merely of specific 

 importance. 



The valves, when viewed inside with the umbo upward, 

 recall the aspect of a bat, the outwardly recurved auricles 

 representing the ears. 



The three valves upon which this description is based have 

 been presented to the British Museum by Mr. J. H. Ponsonby. 

 He informs me that he received them from Tasmania under 

 the name of Pythina Deshayesii^ and therefore it seems likely 

 that this form is wrongly recognized there as that described 

 by Recluz. 



EXPLANATION OF PLATE XIII. A. 



Fiy. A. Mylitta miriculata. Left valve, iuterior. 

 Fi(j. B. „ „ Itight „ „ 



Fiy. C. „ „ Left ,, exterior. 



Fiy. D. Mylitta Stutvei. Left valve, iuterior. 

 Fiy. E. „ „ Kight „ „ 



Fiy. F. „_ „ ..».'> exterior. 



Fiy. G. Mylitta Deshayesii. Right valve, exterior. 



