TROCHUS. 67 
and inside pearly; diam. from 1 to 33; 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- 
ty; diam. 13. W. 29. 88. 
T. magus. Somewhat turban-shaped, with 
transverse rather undulated striz; 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. ?. 
B. W. 28. 34. 
T. arGyrostomvs. Conoid, black, with 
longitudinal oblique undulated furrows, somewhat 
roughened by minute oblique striz ; whorls con- 
vex ; beneath imperforate, stained with green and 
red, and plano-convex ; mouth silvery. 13...14. 
W.. 29. 89. 
T. niLoricus. 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. 33. W. 28. 1. 
T. pyRAMIDALIS. Conic-pyramidal, tuber- 
culiferous, varied with ash-colour and red; with 
