An Intro to Shells

My first real post will be about shells.
( I promised something ocean related, right?)

Shells are animals that are called mollusks. In all there are five types of mollusks:

Gastropods, Bivalves, Tusk Shells, Chitons and Cephalopods.

Gastropods are the mollusks with a single external shell. They are the big conchs and whelks, as well as the small periwinkles.

 

This shell here is a Banded Tulip. As you can see its alive. The operculum (trap door) is slightly open and you can see the mollusks body inside. I found it on Sanibel Island at low tide, last March.

 

Next, Bivalves.

These mollusks are kept inside by two shells that are hinged together. Examples are scallops, cockles and quahogs.

 

 

Atlantic Giant Cockles can be up to 5 inches across when adult. In the photo above you can see both shells and the animal inside. The round hole is probably the breathing tube.

 

Tusk Shells, well, look like elephants tusks. I've found them before, but they are so fragile that I never ended up bringing them home. Sadly, I don't have pictures of them.

 

Same with chitons. Chitons are actually made of eight valves that are surrounded by a girdle. They can be pretty small and I have NEVER found one. Chitons are on my "To Find" list.

 

Finally, cephalopods. Only about half a dozen different species from this class have an outer shell. The most well known are the nautiluses. Other members of this class are the squid, octopus and cuttlefish.

Cephalopod shells, such as Argonauts are actually egg cases. But they usually only wash up on shore after storms. Again, these are on my "To Find" list.

 

As a last note, some of you might ask what shells are on my "To Find" list.

Well, all of them, actually!

I have a pretty big shells collection at home, but most of the shells are from the North American East Coast and the Gulf of Mexico. In short, all the shells that I have not yet found and brought home are on my "To Find" list.

 

Happy Wednesday!

Yaroslava :D