Shells

A Bivalved Snail?

When discussing mollusks with members of our staff, volunteers, and visitors, I always caution them that sweeping generalizations about our beloved animals almost never work. We should be prudent and avoid saying “all marine snails have gills,” or “clams always make their homes on sand,” and so on. Exceptions abound! A standard example includes the members of the gastropod family Juliidae, minute marine snails that have their shells consisting of two separate hinged parts, or valves, just like a

Beyond Shells: The Giant Rock Scallop

The Giant Rock Scallop, Crassadoma gigantea, is another nice highlight from the cold-water touch pool at the Museum. The fact that many species of scallops can swim, relying on bursts of jet-propelled water, always comes up when we talk about the cool things mollusks do for a living. But Giant Rock Scallops are large scallops that don’t swim, spending instead their adult lives attached to hard surfaces such as rocks. Like their swimming relatives, Giant Rock Scallops have a large number of small

Alphabet Cone and the Seven Chitons!

Shell Museum friend and photographer Amy Tripp captured this great image of seven Eastern Beaded Chitons, Chaetopleura apiculata, "hitchhiking" on an Alphabet Cone snail, Conus spurius, on Kice Island, to the south of Marco Island, Florida. Chiton shells are divided into eight ( or very rarely seven) plates, or valves. They belong to a class of mollusks named Polyplacophora (from the Greek words for "many," "plates," and "bearers"). The plates are interlocked, and are surrounded by a fleshy tis

Clench, Cecelia, Tucker, and the Cat!

In a 1974 photo, Shell Museum Founding Director and renowned shell-book author R. Tucker Abbott (holding the cat) is accompanied by his wife Cecelia and Harvard’s renowned shell scientist William J. Clench (holding the cat’s right paw!). In the mid-20th century, Bill Clench was a mentor and graduate studies advisor at Harvard University's Museum of Comparative Zoology to an entire generation of American malacologists, including Tucker. In the summer of 1921, as a graduation present from his fath

Beyond Shells! The Red Turban Snail

One of the species we display in the cold-water touch pool of our Beyond Shells! exhibition is the Red Turban Snail, Pomaulax gibberosus (Dillwyn, 1817), a gastropod from the rocky shores of the West Coast of North America, where it is found from Mexico to Alaska. Red Turban Snails live from the low-tide zone and down to 80 m (about 260 ft) depth, in the cold waters of its native range. The species is usually associated with stands of Giant Kelp, Macrocystis integrifolia, on which it grazes. The

Carrier Snails!

Carrier snails (family Xenophoridae) are gastropods that attach other shells, pieces of corals, or little pebbles to their own shell. To do that, a carrier snail holds the object with the front part of its foot, adjusting it to an adequate position along the last shell whorl, where it will then be “glued” with fresh shell material secreted by the snail's mantle. Carrier snails are cousins to true conchs in the family Strombidae: The image below shows the general aspect of a carrier snail body, w

Metamorphosis in a Sea Snail

In a way that is analogous to what happens when a caterpillar becomes a butterfly, the change in lifestyle from a pelagic (open-water dweller) larva to a bottom-living adult is also known as metamorphosis. The illustration presents three shell-growth stages of an Atlantic Gray Cowrie, Luria cinerea (Gmelin, 1791). From left: the planktonic (free-living) larval shell; juvenile shell briefly after settlement to the bottom-living stage; and adult shell. They are all so different, yet all are stages

Cowries are Cool!

Throughout human history, the enjoyment of shells and curiosity they spark have been the foundation for the science and better understanding of mollusks. And no other group of shells evokes more interest and appreciation than cowries (family Cypraeidae). Their “egg-shaped” shells are usually smooth, glossy, and their weight “feels” just right when held in one's hand. From time to time the living snail covers the shell from both sides of a slit-like opening, and the shell-making mantle repairs bl

Shell of the Week: The Punctate Mangelia

The family Mangeliidae includes a very large number of microgastropods, most of which parade elegant, elongate shells. Kurtziella limonitella (Dall, 1884) grows to 9.5 mm (about 0.4 inch). The shell sculpture in this species comprises about 8–9 ribs on early whorls that increase in number to 14–15 on the last whorl of adult individuals. The microsculpture consists of fine spiral cords crossed by axial grooves; the intersections form little beads that impart a frosty appearance to the shell surfa

Shell of the Week: The Wide-coil Wentletrap

Today, I want to introduce the last species of our three-part series on open-coiling, the Wide-coil Wentletrap, Cycloscala echinaticosta (d’Orbigny, 1842), a species found in the tropical western Atlantic Ocean. In this species, the degree of coiling “openness,” or the distance from one whorl to the next, can vary wildly among individual shells. The possible advantages for these species to "wear" open-coiled shells have not yet been fully explored by malacologists. #widecoilwentletrap #cycloscal