ERRATA. 



While this work has been passing through the press, the 

 following typographic errors have been noted, none of which, it 

 will be observed, materially affect the phrases in which they 

 occur: — 



Page 34, 12th line from bottom: volutions for volutions. 



94, 3d paragraph: perculiar for peculiar; specimems for 



specimens. 

 104, ist line: compressa for compressus. 

 106, 9th line: gainesensis for gainesense. 

 113, middle of the page: plantion for plantation. 

 Plate 6, fig. 16: The Photo-Engraving Co. carelessly cut off 

 the line showing the natural size of the shell. 

 It is magnified 3^ diameters. 

 12, Explanation of figs. 4 & 5 should be followed by f's; 

 the last z in periscelidium should be omitted.. 



