Beautiful Shells of New Zealand Part 2

~CALLIOSTOMA TIGRIS~ (Plate VI.).--Fig. 1 (late Zizyphinus tigris) is a whitish sh.e.l.l, striped or dotted in rows with red. Although sometimes over two inches across, the sh.e.l.l is thin and light. Its glistening interior, and shapely lines, make it one of our most handsome sh.e.l.ls.

These sh.e.l.ls are sometimes found at low water mark, under and amongst rocks in harbours, as well as amongst kelp in the surf. When once a rock, or small patch of rocks, frequented by them is found, subsequent visits in the spring or early summer will nearly always be successful.

It is common to both Islands. During the hot weather of summer, they apparently move to below low-water mark, and remain there in the deeper water until the winter. I obtained a considerable number of excellent specimens from a strip of rocks near the water tank at the entrance to Tauranga Harbour, but never found them except in spring or early summer.

The Maori name is Mata-ngo-ngore, which name is also used for the Cantharidus family, on Plate VII.

~CALLIOSTOMA SELECTUM~ (Plate VI.).--Fig. 2 (late Zizyphinus cunninghamii) is about the same width, but not the same height as the Tigris. The colour is white, with pale red spots arranged in rows around the spire.

~CALLIOSTOMA PELLUCIDUM~ (Plate VI.).--Fig. 3 (late Zizyphinus selectus) is a whitish sh.e.l.l, covered with chestnut-coloured spots and splashes.

It is about 1-1/2 inches across.

~CALLIOSTOMA PUNCTULATUM~ (Plate VI.).--Fig. 4 (late Zizyphinus punctulatus) is the commonest and least fragile of this family. It is seldom more than 1-1/4 inches across. Its rounded whorls, and prominent chestnut and white granules, make it easily distinguishable.

~TROCHUS VIRIDIS~ (Plate VI.).--Fig. 5 is a greenish, cone-shaped sh.e.l.l.

The interior is nacreous, and the exterior covered with coa.r.s.e granules.

The base, which is flat, is greyish. The figure but faintly shows the contour of this sh.e.l.l, which is a perfect cone. The young differ somewhat from the adult sh.e.l.ls, and have a bright pink tip to the spire.

In the plate the upper sh.e.l.l is a young one, and the two lower are adults. They are found amongst rocks at low water mark, in harbours, as well as in the surf. It is very difficult to extract the animal from the sh.e.l.l. Its maximum size is one inch across.

~TROCHUS TIARATUS~ (Plate VI.).--Fig. 6 is usually white, with large grey or brownish-purple dots and bands on both the upper surface and the base, but it is a very variable sh.e.l.l. It is seldom as much as half an inch in length, and has a nacreous interior. It is covered with fine granules, and the base is flat. It appears to live slightly below low water mark, and can be easily obtained by dredging in harbours. The cup-shaped hollow at the base of the spire is much more p.r.o.nounced than in the Viridis.

There is another not shown on the plate, the Trochus chathamensis, a small white sh.e.l.l, with pink or brownish-purple markings, that hitherto has only been found in the Chatham Islands.

~ETHALIA ZELANDICA~ (Plate VI.).--Fig. 7 (late Rotella zelandica) is a well-polished, smooth sh.e.l.l, washed up in large numbers on the ocean beaches. The colours of the upper side vary, but are usually chestnut or purple waving lines on a yellowish-white ground. On the base is a circular band of purple round the columella, which is white. The interior is nacreous. Occasionally a sh.e.l.l is entirely pink, and then the circular band on the base is pink also. The largest sh.e.l.l I have seen was nearly one inch across, and, being very flat, would be only half an inch high. They appear to live in sandy ground, below low water mark in the ocean; and a dredge if drawn over one of their favourite spots will be filled with them. I have dredged half a bucketful at one cast between Karewa and Tauranga in five fathoms of water. The former name was Rotella zealandica, and Rotella, meaning a little wheel, well described the appearance of the sh.e.l.l, the waving line representing the spokes.

~NATICA ZELANDICA~ (Plate VI.).--Fig. 8, a yellowish or reddish-brown sh.e.l.l, with chestnut-brown bands, the interior being pale brown, the mouth and its vicinity white. It is a clean, bright little sh.e.l.l, upwards of an inch across. Those in the ocean are lighter in colour, and larger and more solid than those found in harbours. As the tide falls in harbours, they conceal themselves near low water mark, especially in the vicinity of marine gra.s.s banks. When the tide is rising on a warm, sunny day, they spring out of the sand, dropping sometimes two or three inches from where they had been concealed. The operculum is h.o.r.n.y, with a sh.e.l.ly outer layer; and the animal is prettily mottled and striped red and white.

There are two other Natica found in New Zealand, neither of which exceeds one-third of an inch across, and in shape are very like the N.

zelandica. The Natica australis is a brown or grey sh.e.l.l, and the Natica vitrea is white.

~NERITA NIGRA~ (Plate VI.).--Fig. 9 (late Nerita saturata) is a heavy, solid blue-black sh.e.l.l, with a whitish interior. This sombre-looking member of a handsome tropical family (of which the bleeding tooth Nerita is the best known) is sometimes over an inch in length, and found in large numbers clinging to the surf-beaten rocks of the North Island, quite up to high water mark. The operculum is sh.e.l.ly and prettily mottled with purple. This sh.e.l.l will stand boiling water, and, in fact, boiling water is required to kill the animal, which is quite as tenacious of life as an oyster. The Maori name is Mata ngarahu.

~AMPHIBOLA CRENATA~ (Plate VI.).--Fig. 10 (the New Zealand winkle), lately known as Amphibola avellana, is an uneven, battered-looking sh.e.l.l of a mixed brown and purple colour, the interior being purple and the mouth whitish. It is an inch or more in length. Most mud flats up to high water mark are strewn with Amphibola. The natives eat this sh.e.l.lfish, which they call t.i.tiko or Koriakai, in large numbers; but the muddy flavour, according to our ideas, makes it unpalatable.

~MONODONTA SUBROSTRATA~ (Plate VI.).--Fig. 11 is a yellowish sh.e.l.l, about half an inch across, and is usually found near half-tide mark in harbours. The exterior is covered with black or bluish irregular bands.

The interior is nacreous, and of a greenish colour, with a white patch round the columella.

~MONODONTA AETHIOPS~ (Plate VI.).--Fig. 12 is a purplish-black sh.e.l.l, tesselated with white between the grooves. These grooves look like lines in the plate. The interior of the mouth is white. Besides being usually covered with vegetable growth, part of which is seen in the ill.u.s.tration, the point of the spire is frequently worm-eaten and defective. This is the usual state in which all sh.e.l.lfish that herd together are found. It is upwards of an inch across, and found in large numbers amongst rocks, especially at the entrance to harbours, and from half-tide mark downwards.

~MONODONTA NIGERRIMA~ (Plate VI.).--Fig. 13 has a smooth, purplish-black exterior, sometimes with small blue spots. The interior is white, and the sh.e.l.l about half an inch across.

~MONODONTA LUGUBRIS~ (Plate VI.).--Fig. 14 is a thick, solid black sh.e.l.l, sometimes over half an inch across, and covered with coa.r.s.e, irregular granules. The interior is white. This sh.e.l.l is found in large numbers under stones, at the entrances to harbours and sheltered beaches, almost up to high water mark.

There are six or seven other Monodonta in New Zealand, but they are small, and the four above described are the ones most likely to be met with.

~TURBO GRANOSUS~ (Plate VI.).--Fig. 15 is a reddish-purple sh.e.l.l, varied with white, and is sometimes over 2-1/2 inches across. The specimen photographed was much below the average size. The exterior is covered with well-defined rows of granules, while the interior is iridescent.

It is found on rocks in the open sea in both Islands, but is a rare sh.e.l.l. The operculum is white and sh.e.l.ly.

~TURBO HELICINUS~ (Plate VI.).--Figs. 16 and 17 (late Turbo smaragdus) is a blackish-green sh.e.l.l, found in great numbers at half tide mark on rocks all over New Zealand, especially at the entrance to harbours and in sheltered bays. Some are as much as 2-1/2 inches across. The inside is white and glistening. The operculum is a solid, round, sh.e.l.ly one, with a greenish centre. In some specimens the outer side of the whorl, instead of being round and smooth, has two or three prominent raised ribs or bands on it. This variety is called Tricostata, and is represented by Fig. 16. I am inclined to believe it is only the young form of the ordinary variety. The Maori name is Ata marama.

~ASTRALIUM SULCATUM~ (Plate VI.).--Fig. 18 (late Cookia sulcata) is a pinkish-brown sh.e.l.l, sometimes over 3-1/2 inches wide. The interior is pearly, and the operculum is sh.e.l.ly, solid, and white. The laminae which cover the sh.e.l.l are easily bleached off, and when the sh.e.l.l is cleaned it has a handsome appearance. It is found in considerable numbers at low water mark amongst rocks on exposed beaches all over the North Island.

The Maori name is Kakara or Kaeo, both of which names are also given to the Purpura haustrum (Plate II., Fig. 11).

~ASTRALIUM HELIOTROPIUM~ (Plate VI.).--Fig. 19 is generally known as the circular-saw sh.e.l.l, and, although found all over New Zealand, is comparatively rare. It is reddish-purple, with an iridescent interior, and is sometimes over four inches in width. The sh.e.l.ls on the plate are adults. The spines of the younger sh.e.l.ls are much longer than those of adults. The best specimens have been dredged by oyster boats.

Plate VII.--Figs. 1 and 2 are Janthina, or violet sh.e.l.ls, representatives of which are found all over the warmer parts of the world. The Janthinae live in great numbers on the surface of the ocean, being unable to sink, and are swept by gales and currents in every direction. At intervals, after very heavy gales, they come ash.o.r.e in the Northern part of New Zealand in cart-loads; but after any ordinary gale a few specimens can be procured amongst the gra.s.s cast up by the highest waves. The animal, when touched, emits a quant.i.ty of violet-coloured fluid, the same colour as the sh.e.l.l. The sh.e.l.ls are very light and fragile. A singular provision for its eggs is found attached to the female Janthina, in the shape of a float, or raft, to the under surface of which the eggs in little bags or capsules are attached, and there they remain until hatched.

~JANTHINA EXIGUA~ (Plate VII.).--Fig. 1 is the smallest of the Janthina found in New Zealand, being rarely half an inch in width. The whorls are more rounded than in the other two varieties, and the spire is usually the same violet colour as the mouth, and the grooves on the sh.e.l.l are deep and prominent.

~JANTHINA FRAGILIS~ (Plate VII.).--Fig. 2 is sometimes over an inch in width, the spire being much lighter in colour than the rest of the sh.e.l.l, frequently indeed being white. The grooves on the sh.e.l.l are fine, but clearly visible.

There is another variety occasionally found in New Zealand, the Janthina globosa, like the Janthina exigua in shape, but larger, and the grooving being very faint the sh.e.l.l has a glistening appearance. This variety is rare.

~CANTHARIDUS IRIS~ (Plate VII.).--Fig. 3, from Iris, a rainbow, well describes the colour of this pretty little sh.e.l.l, seldom more than one and a-half inches in length. Pink, purple, yellow, and red seem to be the prevailing colours; and they are arranged in irregular waving lines on its smooth and polished surface. The interior is highly iridescent.

It lives amongst seaweed and rocks below low water mark. The Maori name is Mata-ngo-ngore, which is also used for the Calliostoma sh.e.l.ls on Plate VI.

~CANTHARIDUS TENEBROSUS, var. Huttoni~ (Plate VII.).--Fig. 7 is a little bluish-black sh.e.l.l, about a-third of an inch long, with fine striae or grooves running down the whorls. Alive, it is found in great numbers at low water on marine gra.s.s banks in harbours, and seems to be very active, as the anchors and cables of boats, moored for a few hours over one of their favourite haunts, will be liberally sprinkled with them.

~CANTHARIDUS PURPURATUS~ (Plate VII.).--Fig. 8 is a heavier and rougher sh.e.l.l than the Iris, and of a rose-pink colour. Sometimes the whole sh.e.l.l is of this colour, but frequently only the top of the spire. It also lives amongst seaweed and rocks; but when living on gra.s.sy banks in harbours seems to lose its pink colour and become a pale grey.

~CANTHARIDUS FASCIATUS~ (Plate VII.).--Fig. 9 (lately known as Bankivia varians) is found in Westland. White, green, rose, purple, or black in colour and plain or banded, and sometimes even with longitudinal wavy lines. It is about half an inch in length.

All of the Cantharidus family have beautiful nacreous interiors, and are the favourite New Zealand sh.e.l.ls for necklaces and bracelets. When cleaned with acid, they are much admired. We have six or eight other varieties of Cantharidus, but they are small, and are not figured on the plate.

~TARON DUBIUS~ (Plate VII.).--Fig. 4 is a sh.e.l.l about three-quarters of an inch long, and found under rocks in partly-sheltered harbours. The exterior varies from chocolate to black. The interior varies between purple and white. The lip end of the spire is usually reddish.

~LITORINA CINCTA~ (Plate VII.).--Fig. 5 is a semi-amphibious sh.e.l.lfish common to both Islands. It is found amongst rocks in the open sea near high water mark. The exterior is brown, or bluish-black, with fine grooves or lines round it. The interior is violet, and the extreme length about 3/4 inch.

~LITORINA MAURITIANA~ (Plate VII.).--Fig. 6 is a very common sh.e.l.l in the North Island, where it is found on rocks in the open sea, or in harbours up to, and even above, high water mark. The sh.e.l.l is under half an inch long, and usually not more than a quarter of an inch. The colour outside is bluish-white, with a broad spiral band of dark blue. The interior is violet.

~DAPHNELLA LYMNEIFORMIS~ (Plate VII.).--Fig. 10 is a very thin, whitish sh.e.l.l, with irregular brown markings, and is often dredged up in the vicinity of Auckland. Its extreme length appears to be 1-1/4 inches.

~SURCULA NOVae-ZELANDIae~ (Plate VII.).--Figs. 11 and 12 (late Drillia zelandica) is a pale rose-coloured sh.e.l.l, nearly 1-1/2 inches in length.

It belongs to the Pleurotoma family, any of which can easily be identified by the notch in the outer lip, as shown near the centre of the figure. All of this family live below low water mark, and are obtained by dredging. It is found in both Islands.

~SURCULA CHEESEMANI~ (Plate VII.)--Figs. 15 and 16 (late Pleurotoma) is a sh.e.l.l varying from pale pink to brown in colour. Interior rose or purple. The spire end is usually smooth. It is found in Auckland, and is about one inch in length.

~SOLIDULA ALBA~ (Plate VII.).--Fig. 14 (late Buccinulus kirki) is a whitish sh.e.l.l, found in the North of Auckland. Its extreme length is 3/4 inch.

~POTAMIDES SUB-CARINATUS~ (Plate VII.).--Fig. 13 (late Cerithidea subcarinata) is a dull black sh.e.l.l seldom over half an inch long. The colour is usually concealed by the reddish-brown epidermis. The interior is dark purple.

~POTAMIDES BICARINATUS~ (Plate VII.).--Fig. 19 (late Cerithidea bicarinatus) is a reddish-brown or purple sh.e.l.l, covered with a blue or brown epidermis. The interior is purple. It is found in the North Island in large numbers on banks of sand mixed with mud near high water mark.

Its extreme length is one inch.

~SCALARIA ZELEBORI~ (Plate VII.).--Fig. 17 is the New Zealand representative of the Wentletrap family. It is a pure white sh.e.l.l, sometimes over an inch in length. The numerous ribs across the whorls are very prominent, and look like the steps of a ladder, whence it derives its name. It lives in the ocean below low water mark, and I have dredged it up with the Ethalia zelandica (Plate VI., Fig. 7). The Maori name is Totoro.

~SCALARIA TENELLA~ (Plate VII.).--Fig. 18 is a dirty yellow, almost transparent, sh.e.l.l about a-third of an inch long. There is usually a pale brown band near the centre of the whorl. Found about half-tide mark in sheltered water.

~TEREBRA TRISTIS~ (Plate VII.).--Fig. 20 is a bluish or blue-grey sh.e.l.l, slightly over half an inch in length. The interior is brownish-white, with a yellow band in the centre of the whorl. The varices on the exterior are not so prominent as in the Potamides (Fig. 13).

~TENAG.o.dES WELDII~ (Plate VII.).--Fig. 21 (late Siliquaria australis) is a small white sh.e.l.l, not more than one inch long. It is found in Hauraki Gulf.