FAMILY TURRITELLIDM. 



Animal with a short broad rostrum ; long, subulate, diverging 

 tentacles, the eyes slightly prominent at their external base ; 

 mantle margin fringed, slightly plicate or channeled in front and 

 on the right side ; branchial plume single, very long ; foot very 

 short, truncate in front, attenuated and obtuse behind, grooved 

 beneath, operculigerous lobe simple. 



The lingual dentition varies in the number of margined teeth ; 

 thus for T. acicula, the marginals are suppressed, and. the for- 

 mula is 0-1-1-1-0 (PI. 59, fig. 30); for T. ungulina, 2-1-1-1-2, 

 (PI. 30, fig. 11), and for T. triplicata 3-1-1-1-3 (PI. 59, fig. 29). 

 T. lactea, representing the group Mesalia, has the marginal teeth 

 with smooth edges, formula 2-1-1-1-2 (PL 30, fig. 12). 



Shell spiral, not umbilicated, spire very long, of numerous 

 whorls, with revolving striae or carinations, and curved growth- 

 striae ; mouth obliquely oval or subquadrangular, usually entire, 

 lip not thickened. Operculum multispiral. 



The genus Eglisia, Gray, 1840, included by man 3^ conchologists 

 in this family, belongs apparently to the Scalariidae. Yon 

 Maltzan has recently described a genus Smithia, 1883, which is 

 said to have a multispiral operculum, and is placed by him in 

 Turritellidae, yet in the scalariform whorls, depressed superior 

 portion, etc., it appears to be simply an exaggeration of the char- 

 acters of Eglisia ; and it is connected with that group by Fischer. 



The Turritellidae have been monographed by : 



Kiener. Coquilles vivantes. 34 species. 



Reeve. Conchologia Iconica. 68 species. 1849. 



Boury has monographed the genus Mathilda, in Journal de 

 Conchyliologie, 1883. 



Synopsis of Genera. 

 Genus TURRITELLA, Lam., 1799. 



Shell pyramidal, the numerous whorls spirally striated or 

 ridged, crossed by arcuated growth-lines, spire very long, aper- 

 ture oval or subquadrangular, entire, lip thin. Operculum with 

 fimbriated margin. 



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