217 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. VILL. 
running spirally round the centre of each whorl ; colour, rusty yellow. 
A good specimen would be 5” to 6” long. 
NATICID AL. 
Shining, globular, thinnish shells, many of them of great beauty ; 
last whorl envelops greater part of shell ; mouth large and somewhat 
semi-circular or auriform. Shells are umbilicated, z.¢., the axis or 
columella round which the whorls are formed is more or less hollow. 
Natica didyma (Bolten) attains a good size, yellow or fawn- 
coloured young shells and apex often with a leaden hue; easily known 
by a chocolate-coloured callosity nearly covering in the umbilicus, 
this callosity having a central groove running across it. I am indebted 
to Mr. E. A. Smith, of the British Museum, for the information that 
this shell is figured in Reeve’s Conchologia as Chemnitzi lamare- 
kiana, petiveriana, and problematica. 
Natica lineata (Lam.).—White, with irregular, slanting, closely set 
stripes of reddish-brown colour running across the whorls of the 
shell ; umbilical area pure white. 
Natica maculosa (Liam.).—A smaller and very common shell, with 
brown or purple spottings or streaks. When the shell is bleached these 
spots become reddish. 
Natica rufa (Born.).—A plain, yellow-brown shell with a distinct 
band: of white running spirally round centre of whorl ; base very 
white. 
Mammilla zanzibarica (Recluz.).— A white, oblong, very thin shell, 
with a faint central band of colour on last whorl ; mouth very large 
and auriform ; umbilicus nearly covered in by a long purple or brown 
recurvement of shell. 
CAPULIDZ. 
There is one specimen of this curious family which should be men- 
tioned. It [Lrgea walshi (Herm.)] lives inside dead shells and adapts 
itself in shape to its situation like the oysters. It is most often a flat, 
white, oval shell, looking like a bivalve, but the inner side is porcella- 
neous, and has a protruding lip, which forms a cavity and, no doubt, 
serves to protect the vital parts of the animal. 
PLANAXID anp LITTORINIDA. 
The authority I am following does not seem to give the former 
