TROCHUS. 67 



and inside pearly ; diam. from 1 to 3 ; imper- 

 forate. W. 29. 105. 



T. TUBER. Imperforate, conoid, thick, with 

 the whorls strongly plaited above, and their lower 

 margin nodulous; greenish, shaded with brown 

 and white ; beneath rather convex ; inside pear- 

 ly; diam. IJ. W. 29. 88. 



T. MAGUS. Somewhat turban -shaped, with 

 transverse rather undulated striae ; whorls plaited 

 on their upper margins ; umbilicus oblique ; sur- 

 face deep; colour pale ash or flesh-colour, ele- 

 gantly marked with broad undulated purplish- 

 pink stripes; beneath rather convex; diam. J. 

 B. W. 28. 34. 



T. ARGYROSTOMUS. Couoid, black, with 

 longitudinal oblique undulated furrows, somewhat 

 roughened by minute oblique striae ; whorls con- 

 vex ; beneath imperforate, stained with green and 

 red, and plano-convex ; mouth silvery. Ij . . . If. 

 W. 29. 85. 



T. NiLOTicus. Conic -pyramidal, dilated at 

 the base, thick and ponderous, smooth, white, 

 with longitudinal reddish-brown streaks ; spotted 

 with crimson beneath ; columella arcuated, trun- 

 cated beneath, and dentiferous above ; a false 

 umbilicus; diam. 3^. W. 28. 1. 



^•T. PYRAMIDAL.IS. Couic- pyramidal, tuber- 

 culiferous, varied with ash-colour and red ; with 



