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Cowrie seashells are often prized in family shell collections and are admired for their smooth, glossy, porcelain-like appearance and feel and their bright, colourful patterns. Cowries are usually egg-shaped, with a flat under surface divided by a long, narrow aperture that often has toothed edges that may be coloured. The anterior end is more narrow and the spire is usually only visible in the juveniles of most species. Cowrie, or cowry, is the common name given to both the family of Cypraeidae for marine gastropod molluscs, or sea snails, and to their shells.
Most cowries live in the tropics and warmer seas, but some are found in more temperate seas as well.
Reproduction: Research is continuing into the reproduction of the cowrie, but it is thought that, like some other marine molluscs, it is a hermaphrodite. The eggs and sperm are released into the water and fertilization takes place without contact. Many eggs are placed in separate capsules and the parent broods over clusters of these. When the larva hatch, the veliger are free swimming. After about four weeks they sink to the sea floor where metamorphosis takes place. The shell develops but in the juvenile the aperture is wide. It gradually narrows over a period of about a year until the shell takes the adult shape.
Hundreds, even thousands of years ago the cowrie was used in some countries as a religious symbol and as currency for trade, payment and even for taxation. Although its use as money had been superseded in most areas. the cowrie is still looked on as valuable for a variety of uses.
Names for Cowries
There are over one hundred and sixty different types of cowries and their names are interesting as they often describe the shell's appearance, the habit of the animal, its use, or the name of the person who first found it.
Most of the cowries in my collection are from the western Pacific: Australia, Papua New Guinea and Fiji.
Cowries Named for Their Appearance:
- Animals: The popular Tiger Cowrie (above) is one of the largest and is named for its markings, as is the Lynx Cowrie (above), which usually grows to about an inch or an inch and a half. The Tortoise Cowrie (below) grows to about four inches and really does look a little like a tortoise while the Mole Cowrie (below) has the dark markings front and back.
- Shape: The Hump-back Cowrie grows to about three inches and is noticeably higher in shape. The Nucleus Cowrie grows to three-quarters of an inch and is rounded in appearance.
- Markings: The Gold-ringer Cowrie grows from half to one inch and is very common. The gold ring is clearly visible.
Cowries Named for Their Habits:
The Wandering Cowrie.
Cowries Named for Their Use:
The Money Cowrie is very common. It grows to an inch and is unique with its colour and bumpy edges.
Cowries Named for The Person Who Found It:
The small Bartletti Cowrie.
Cowries as Currency
In times past shells were used as currency in almost every continent in the world and in many of the islands. A variety of shells were used in different countries, but the most common were the cowries and the most used of these was the cypraea moneta. This species was especially abundant in the Indian Ocean and was collected and taken to centres for dispersal in several countries.
Cowry money was currency in trade in Africa, America, Arabia, in parts of Asia including China and India, and in many of the Pacific Islands, including Papua New Guinea.
- Africa: Cowries were used extensively in the slave trade and as currency in a number of African countries. It was even used for taxation in some countries.
- America: Cowries were used extensively, firstly as decoration and later in some places as currency by indigenous people in North America, especially along the western seaboard, right from Alaska to California for nine thousand years. They were also used in South America in countries such as Brazil.
- Arabia: Cowries were used as legal tender by Arabian traders.
- Britain: Cowries were imported and used widely in the slave trade.
- China: The cowrie was the earliest currency used in China, right from the sixteenth century BC. As they were scarce, copies were made, sometimes in silver or gold. Cowries were also used as decoration of clothing and has been found in tombs as money for the dead. The Chinese Character for money is based on the cowrie shell.
- Fiji and Other Pacific Island Nations: The cowrie was used as decoration, currency and as a status symbol until quite recently.
- India: Until comparatively recently cowries were used and exchanged for rupees.
- Papua New Guinea: In some places, including New Britain, cowries are still used as currency and are exchanged for Kina.
Other Uses for Cowries
In past times, cowries were used widely especially in religion, fortune-telling, a sign of rank, in games and for decoration. Today they are still used in a number of different ways.
- Religion: One type of cowrie is considered sacred by the Ojibway people of North America and is used in ceremonies. They have been used as lucky charms and as symbols of fertility.
- Fortune-telling: In Brazil and some other countries, cowries are shaken in the hands and thrown onto a flat surface for the purpose of fortune-telling. They are also used for divination in parts of India.
- Sign of Rank: In Fiji, the golden cowry was worn by chieftains as a sign of rank.
- Games: Cowries have been used as a type of dice in board games and other games.
- Decoration: Cowries are used as decoration as jewellery, on clothing, head-gear, handbags, plant-hangers, around picture-frames and in many other ways.
Note: Until quite recently the Tiger Cowrie was used in Europe for stretching socks and stockings as they were being darned.
Around the world, there are several types of cowrie that are rare. Perhaps one of the most rare is the C. Bartletti, which measures about three-quarters of an inch. Viewed from the top it has a lovely lilac coloured edge and this is continued across the underside.
The Rev. H. K. Bartlett worked as a missionary with the Australian Methodist Overseas Mission for a number of years. He was greatly interested in the local environment of the southern islands off eastern Papua New Guinea and very knowledgeable about shells, especially cowries. In about 1946 he found a new species of cowrie. It was named C. Bartletti for him. There are two Bartletti Cowries in the Museum of South Australia and about five in private collections, so it is very rare indeed.
A Fun Use for a Cowrie
Note: Many cowries are fairly similar in appearance. If any mistakes are found in the naming of the cowries shown above, please let me know in a comment so it can be rectified.
Shells of the Sea
- Helmet Seashells
The Helmet seashell is a member of the Superorder of Caenogastropoda, as is a smaller member of the Helmet family, the Bonnet seashell. Because they have been attractive to tourists and collectors and some species are now protected in Australia.
- The Paper Nautilus
The life of the paper nautilus and its delicate egg-case is discussed, concluding with a warning that global warming may contribute to its extinction.