NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 2/ 



The type, U.S.N.M. No, 561627, comes from the Pliocene deposits 

 of North St. Petersburg, Fla. It has 9.3 whorls remaining and meas- 

 ures: Length 4 mm., diameter i.i mm. U.S.N.M. No. 561628 con- 

 tains an additional specimen from the same source and two more are 

 in the collection of the A.N.S.P. 



Genus MORMULA A. Adams 



1863. Mormula A. Adams, Journ. Linn. Soc. London, vol. 7, p. i. 

 1884. Pyrgostylus Monterosato, Nomenclatura generica e specifica di alcune 

 Conchiglie mediterranee . . ., p. 90 (type: Turbo striatulus Linnaeus). 



Pyramidellids having axial ribs and deeply incised spiral lines or 

 grooves ; also irregularly disposed varices on the outer surface, which 

 usually mark internal lirations on the outer lip, or internal lirations 

 of the outer lip only. Sculpture never nodulose. 



Type : Mormida rissoina A. Adams. 



KEY TO THE SPECIES OF MORMULA 



Axial ribs slanting protractively. 



Shell of gigantic size vaiighani 



Shell not of gigantic size. 

 Shell short and stout. 



Shell acutely tapering gardnerae 



Shell not acutely tapering mansfieldi 



Shell not short and stout. 



Whorls very strongly rounded cookei 



Whorls moderately rounded. 



Axial ribs distantly spaced woodringi 



Axial ribs not distantly spaced. 



Shell very slender marshalli 



Shell not very slender. 



Axial ribs fine harrisi 



Axial ribs stout palmerae 



Axial ribs slanting retractively. 



Shell rather stout pilshryi 



Shell rather slender. 



Whorls flattened robcrtsonae 



Whorls rounded teskeyae 



MORMULA VAUGHANI, new species 

 Plate 6, figures 3a, b 



Shell elongate-turrited, very large, cream-yellow. The unique type 

 is a fragment consisting of the last 5.1 whorls, which are rather high 

 and flattened. The whorls are marked by axial ribs, which are slightly 



