somewhat of a dull heliotrope tint, or it may be of a misty 
blue-grey; the base is yellowish and decorated with spiral 
rows of beading. The umbilicus is widely open, and the 
apex of the shell may be seen through the opening. What 
particular function the umbilicus has is rather difficult to 
say offhand, but probably it is a provision of Nature to 
give lightness and strength to the shell by hollowing out 
the columellar pillar, a principle well known to engineers— 
that a hollow pillar is relatively stronger than a solid one 
of similar dimensions. The whorls are also spirally beaded, 
and the spurs are to be seen on the upper whorls of good 
specimens, though the shell is usually so coated with coral- 
line growth that they are hidden. The interior is pearly. 
Large specimens may be as much as four inches across. 
Captain Haultain informs me that fifty years ago, when 
trawling and dredging were not carried out to any extent, 
a good pair of these shells would fetch £60 in the London 
salerooms. At the present day it is doubtful whether they 
are worth as many pence. 
Found washed ashore after gales on sandy beaches; 
the best are only to be obtained by dredging in about 
twenty fathoms. 
Bay of Islands; Mount Maunganui; Tasman Bay; 
Stewart and Chatham Islands. 
ASTRAEA SULCATA (Asiraea, Star-maiden, goddess 
of Justice; sulcata, furrowed).—A rather rough-looking 
shell with a wide base, reddish brown in colour, and with- 
out lustre. Juvenile shells, of about half an inch in dia- 
meter, present a row of short, sharp teeth projecting out- 
wards horizontally around the periphery or widest circum- 
ference of the base. It has rounded ribs with intervening 
rounded sulci, or furrows (hence the specific name), dis- 
posed obliquely down the whorls. The operculum is thick 
and shelly, with a remarkable resemblance to a human ear, 
the rim opaque and most of the remaining portion semi- 
transparent. A specimen shell may be cleaned by remov- 
ing with a penknife, or acid, the external laminations, 
leaving a beautiful white pearly surface, but as this is not 
the natural condition, the shell so treated can only be re- 
garded as a “fake,” suitable to garnish those curious mid- 
Victorian contrivances known as what-nots, but quite out 
of place in a collectors’ cabinet. 
About three and a-half inches across; it is found on 
the coasts of both Islands, on rocky ground near low-water 
mark, or in a few fathoms. 
Mount Maunganui; Chatham Islands. 
an 
Plate II 
No. 13 
Sea Shells 
of New Zealand 
