hell 
vf a ealand 
Plate VIII 
No. 29 
Plate X 
No. 12 
Plate IX 
No, 4-4a. 
DENTALIUM NANUM (dentalium, dim. of dens, a 
tooth; manus, a dwarf)—Commonly known as the Tusk 
shell or Elephant Tooth. It is small, curved, tapering and 
pointed like an elephant’s tusk. At the anterior, or larger 
and open end, the tube is ten-sided, the sides being flat, 
but towards the middle of the shell these flattened sides 
gradually become grooved; proceeding further towards the 
point, the grooves are more pronounced and are separated 
by rather sharpish ridges, the ridges and grooves becoming 
about equal in size. The shell is light horn colour, or 
whitish, and about three-quarters of an inch in length. 
A species of Dentalium shell was much esteemed as a 
charm by the ancient Egyptians, and infants wearing this 
amulet were supposed to be immune to the trials of teeth- 
ing. 
5 Found at the Great Barrier Island; Manukau; Raglan; 
Poverty Bay; Stewart Island; The Snares. 
SOLEMYA PARKINSONI (solen, a razor; mya, a 
mussel).—A narrow, elongated bivalve, the length being 
about three times the depth. The dorsal and ventral mar- 
gins are straight and parallel to each other; the ends, both 
anterior and posterior equally rounded. It is extremely 
fragile, and covered with a very glistening, thin, rich brown 
epidermis which extends well beyond the free borders of 
the shell like a fringe. The glaze of the surface is unusu- 
ally brilliant, so much so that when a specimen in the dried 
state is seen for the first time, one is generally asked if 
the valves are varnished. There are dark bands of colour 
radiating from the dorsal margin to the ventral, distinctly 
showing through the epidermis. It may be as much as 
two inches in length, but an inch and a half specimen is a 
good one. They are found in thick mud, six inches below 
the surface, but it is preferable to find them on the beach 
after a rough sea. 
Throughout New Zealand. Tauranga Harbour. 
NUCULA HARTVIGIANA (nucula, dim. of nux, a 
nut; Hartvig, the naturalist)—A small white, or very 
pale olive-coloured bivalve, only a trifle over a quarter of 
an inch in diameter, most asymmetrical in shape, with a 
rounded ventral border, and sculptured with deep con- 
centric grooves: The interior is a glistening pearly white, 
with a number of teeth arranged in two rows, one on either 
side of the hinge; there are about eight behind and four- 
teen in front of the beaks. Commenting on the diversified 
means by which Nature gains the same ends, Darwin says: 
“Bivalve shells are made to open and shut, but on what 
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