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MONOGRAPH OF THE GENUS 

 LATIAXIS, Sivainson. 



Generic Character. — Testa angulatim fusiformis vel tur- 

 binata, canali extus late umbilicato, varice spirali, exfoliata 

 marginato. — The shells associated in our plate, and mostly 

 supposed to belong to this genus, have one or more of certain 

 characters which link them together so as to form in ap- 

 pearance a natural group. The type is Pyrula Mawcp., re- 

 markable for the breadth of its umbilicated disc in the region 

 of the canal. This character appears more or less in all the 

 species but two, which otherwise resemble the umbilicated 

 species so closely as to be scarcely separable. The exceptions 

 are L. fruticosus, Goulds and L. pagoda, Adams. The species 

 are all peculiarly sloped down towards the angle excepting 

 L. Mawae. 



Species. 



1. MAWiE, f. 9, Gray. — Testa roseo-alba turbinata, spira 

 elevata superne compressa, anfractibus laxatis spiraliter 

 scabroso-sulcatis, angulatis, ad angulum lamiuis trigonis latis 

 crispatis coronatis, supra angulum late subplanulatis, infra 

 medium coarctatis, ad canalem expansis late umbilicatis 

 extus exfoliatis, apertura superne subrotunda, canali oblique 

 tortua. — Of a remarkable form, needing no description for 

 English readers. 



2. Deburghi^, f. 5, Reeve. — Testa subturbinata albida 

 solida spiraliter sulcata ; spira exserta, anfractibus 5 brevi- 

 bus subacute angulatis, ad angulum laminis latis elongatis 

 oblique extantibus sursum acclivibus coronatis, supra angulum 



