Thursday, March 16, 2017

Uses for Sea Shells

  While serious sea shell collectors prefer to display the objects of their passion in cases, on shelves or  by some other means of exhibition, not everyone shares the same desire for displaying shells. A quick trip to one of your local mega-hobby stores will bear this out. On a recent foray to Hobby Lobby for something or other I walked down a nautical themed aisle filled with any number of knick-knacks, including bags of shells. The idea is for the purchaser to use them as accents in various craft-oriented projects such as filling glass jars or faux fishing nets as accents to the decor of a home.
  Normally shells found in such a way are of an abundant quantity and thus extremely common and really serve very little purpose to the ardent collector.
  But crafters have a flair for presentation with such shells, using them to create a table centerpiece, for lamps, for embedding in walls to make back-splashes or to augment bathroom shower tile or framing out a mirror. Parents and teachers also find novel uses for shells by painting and gluing them together to make small sculptures, nightlights or even Christmas tree ornaments. Really, there is no limit to what you can do with sea shells. I even heard of an artist who would take shells such as abolone and crush the pearlescent shells into powder to mix in and use in their paint!
  Bottom line - you don't have to be an avid collector to find and use sea shells to your advantage and enjoyment!

Tuesday, April 19, 2016

Scaphopoda - The Tusks

Scaphopoda or Tusk Shell
Photo from:
http://www.molluscs.at/scaphopoda
  When we think of seashells the first images that might come to mind are generally images of the Queen Conch or Triton's Trumpet or possibly the humble oyster or clam shells. But the shell, often regarded as one of the most numerous in the ocean, is a member of the class of molluscs known as Scaphopoda or more commonly called the "Tusk Shell."
  Along the coasts of the America's the tusk shell was used by natives to make decorative adornments and was often used as currency which every school child knows as "wampum."
  The tusk shell is considered to be related to clams and oysters but unlike it's bi-valve relatives the tusk only has one shell comprised of a calcified material that surrounds the animal within and generally wider at the head (which is buried in the seabed) than at the top which extends above the sediment or sand it is buried in. This shell appears in shape much like an elephant's tusk and therefore it's name, but the similarities end there as it is open at both ends and only grows to about 1.5" in length. 
  The animal within the shell uses a foot to dig into the surrounding sand then enlarges it to move. 
  The primary diet of Scaphopoda's are Foraminifiers, one celled organisms which it captures with thread-like tentacles called captaculas which extend out from the shell and sift through the sand around the foot.
  Adult Scaphopoda's have both male and female sex organs. It releases it's eggs one at a time and then fertilizes them externally. The young will then go through a free-swimming larval stage (known as a trochophore stage) before entering a larval stage (known as a veliger stage), after which it finally becomes an adult.
Anatomy of a Tusk Shell
from:
http://www.ucmp.berkeley.edu
  The Scaphopoda breaths by siphoning water into it's shell opening at the top and circulating it through the mantle cavity by tiny hair-like appendages called cilia with the mantle absorbing the oxygen. When the water is depleted of oxygen it is ejected through the top opening by the animal squeezing the mantle with it's body to close the mantle then allowing new oxygenated water back in when it relaxes and the process repeats.
  In like manner the animals waste is expelled from the anus into the mantle cavity and ejected with the oxygen depleted water.
  Though Scaphopoda do have a heart it is so small as to be almost non-essential since the blood flows freely and is circulated by the movement of the foot as it swells and deflates in it's process of inhaling the oxygenated water and expelling it.

Sunday, February 28, 2016

When you can't find it...

Jenneria Pustulata. Native to the pacific coast the largest of
these shells measures only about an inch in length.
  In January of this year I traveled to Peru for a short vacation in Miraflores (outskirts of Lima). Being a city on the pacific coast I had hoped to do some beach combing while there and I in particular I had hopes of finding at least one shell from the area - the Jenneria Pustulata, a small cowrie with beautiful little "postules" protruding on the anterior side. Unfortnately the coast at Miraflores is not conducive to beach combing, it is strewn with rocks from the size of a kiwi to a grapefruit.
  After an abbreviated attempt on the beach I quickly decided the best place to find the shell would be in a local souvenir shop. Wrong. After days of fruitless searching for a store with such items I discovered that for Miraflores the sea meant very little in terms of tourism and catered mainly to surfers.
  Sadly I departed Peru with no shell to show as evidence of my trip. But all was not lost. After arriving back in the states and getting settled back into my daily routine, I hopped on the internet and in short order tracked one down from one of the many sites I have purchased shells from in the past. In just a few days a package appeared in my mailbox with the ordered shell. Even though I knew the shells were tiny (mine was about 3/4" long) I was still surprised at how small they appeared. The shell I had purchased was absolutely beautiful though and I proudly added it to my collection... a memento of a fabulous trip to south of the equator!

Sunday, September 27, 2015

Another way to collect

  I much prefer, of course, to collect my sea shells myself on excursions to the beach or diving or snorkeling. But unfortunately it is just impractical to think I could collect shells from all around the world by journeying to those locations myself. I'm just not quite that blessed with finances to do such.
  So how then does one collect sea shells if he/she can't actually venture to those places they are found? Shopping on the internet of course! At one time a millennia ago before there was such a thing as the internet we were relegated to finding shells ourselves, thus limiting the extent of our collection to those shells found within our region or the occasional vacation spot, or purchasing them through souvenir stores along the coast. This however was not an expeditious way to collect as most shells that filled the bins at tourist traps were generally lower grade extremely common shells - which we had plenty of in our own collections anyway. Being a Navy brat I occasionally acquired shells from friends in the military who departed for distant shores for up to six months. Occasionally I would receive a gem of a shell. But this method too was quite unsatisfactory. 
  Enter the age of the computer and more specifically the internet. There are many sea shell stores online which makes collecting those rarer shells much easier.
My very own Venus Comb Murex
It lives up to its name - Venus, the Goddess of beauty!
  There are several listed on my "Links" page. Some shells may not only be found in the far corners of the world but they may also be very, very delicate and thus not a shell you would want to find and transport yourself. For me, this was the case with what I and many others consider one of the most beautiful seashells there is - the Venus Comb Murex. I had never actually seen a Venus Comb Murex before but I knew from others and just looking at pictures that they were extremely delicate and to find one without any spines broken is not easy. So I ventured to purchase one from a store online with the stipulation that should just one of its spines be broken upon receipt I would be sending it back. In about a week my package arrived. I was exalted to open it and see this beautiful shell worthy of its name. I knew they were not overly large shells (up to about 5-6 inches is about as big as they get) but what I was not prepared for was their weight - or lack of weight to be more specific. As I gently drew the fragile shell out of it's box and packaging and placed it in my palm I was enthralled at how light it was. Surely more heavy than a feather but certainly not too much more so. The supplier had done me justice and securely packaged this extremely delicate shell.
  While I have shopped online for shells several times and never had a problem with the condition of one when it arrived, I still am wary and expect one day to be disappointed. But even if that day should come, I still would use online shopping to purchase those shells I desire which are physically out of my reach but are worth seeking out and obtaining. And if I ever do get to the other side of the world maybe, just maybe I'll come home with a Venus Comb Murex found by my own hand.
  Happy shelling!

Friday, July 3, 2015

Ode To An Inspirational Teacher

Ms. Viola Perrault
4th Grade Teacher, Pilot, Adventurer,
SCUBA Diver, Shell Collector, and
inspiration to many generations
of students.
  We all have a teacher we recall as being influential in our lives. I was fortunate to have several. One of the earliest ones I recall was my fourth grade teacher at W.T. Sampson school in Guantanamo Bay, Cuba - Ms. Viola Perrault.
  At an impressionable age Ms. Perrault was one of those teachers who instilled excitement into the learning process. She gifted us with a desire to learn more. To this day I recall one of my favorite times of the school day was reading time. She introduced us to stories as varied as the fantastically whimsical Willy Wonka and the Chocolate Factory to the very poignant and grown-up tale of Flowers for Algernon. For myself and every student she ever taught the year-long class project of collecting, classifying, memorizing and displaying a sea shell collection was the highlight of our education.
  Being that we lived in the tropical paradise of Guantanamo Bay we had a veritable treasure trove of opportunities and locations to seek out shells for our projects. Ms. Perrault even coordinated with the Navy to make use of their vessels to take us on field trips to beaches not normally accessible to us. Trying to sleep the night before a field trip across the bay was as pointless as trying to sleep on Christmas Eve - you fought it all night long.
  Over the years the knowledge I learned that very special year has faded. Where once I could rattle off the scientific name of every sea shell I owned, the location in the world where they were found and a plethora of ancillary information, I can now recall just the common names of most shells. But where that knowledge may have faded over time, my love of the sea and marine life and the marine eco-system has not. Now some forty-three years after Ms. Perrault gave me the gift of love of sea-life I find myself once again digging in, researching, classifying, memorizing and building a shell collection to display, both actual and virtual, hopefully educating and passing on the love of the life aquatic to others.
  Thank you Ms. Perrault for the gift you gave me and so many others those many years ago.

Thursday, March 12, 2015

Parts of a Sea Shell

 The Shell  
   Not all molluscs have all the same parts however they do have one part in common - a hard outer protective body - the shell itself. This outer body, or shell, is created by the animal itself. Some malacologists promote the idea that the shell is part of the body and they have a point because without the shell the animal within would soon die, much as we would without our protective shell (our skin). However as a conchologist it is my opinion that the shell is separate part of the animal because the animal within must attach itself at some point within the shell either by use of tendons as a conch or tusk shell does by affixing its tendon to one part deep within the shell, or membranes such as chitons and bivalves do or by simply wrapping a portion of its body onto the inside of the shell and holding on tightly the way cephalopods (such as the nautilus) do. But in each case each mollusc has a hard out protective casing we call the shell.

Security
   Conch and tusk snails have a cartilaginous foot called the operculum which is the outer most part of the body itself. When the animal withdraws into the shell the snail will draw the operculum tight into the aperture or opening securing the soft tender body from most predators. Basically the operculum acts as a doorway the snail can close shut or open to come out. 
   Bivalves have no such feature, instead their body is encased between two opposing hard shells that are hinged at one point - thus the name "BI-valves." When the animal is in danger it uses its powerful membranes within to close fast the two hinged shells making it impenetrable from most predators.
   Chitons are positively one of the most archaic looking creatures found in the sea. They are generally found attached to large rocks and boulders along a rocky shoreline. The chiton actually has several hard outer shells that form plates much like an armadillo. These plates are attached on the underside my strong muscular membranes. The chiton uses other muscular membranes beneath itself to create a powerful suction against the rock and pull the plates down to where they are fastened hard against the rock and extremely difficult to pry off. 

Breathing
   Most conch and tusk shells have what is called a siphonal canal of some kind through which the snail can extend an apparatus to siphon seawater inside in order separate the oxygen in order to breath. It will then pump the oxygenless seawater back through the same siphon.
Since not all conchs and tusk are the same this size, shape, length, location and manner in which they breath are different but most have some form of siphonal canal. 
   Bi-valves have a siphon but no canal on the shell. Most bi-valves use their muscles to pump oxygenated seawater in and out but the siphon is contained within the safety of the shells. 
Diagram of basic gastropod shell partsDiagram of basic gastropod shell parts


   These are the three main parts of most sea shells. When dealing with specific classes each will have different sub-basic parts of the shell. The diagram shown is of a basic gastropod or uni-valve sea shell and breaks down the parts of the shell itself. Even with the gastropods specific families, genus and even as far down as species will all have additional parts not found on other shells. 
   Perhaps in the future we'll examine and break down shell parts even further.

Wednesday, March 11, 2015

Conchology Defined

Shell of the Queen Conch - a gastropod.
 Conchology (pronounced “konk-ology”) is the study of the shell of molluscs. This is not to be confused with malacology - the study of mollusk organisms. Conchology is confined to the study of their shells.
  There are those who view conchologists as just glorified shell collectors. While conchologists can and usually are shell collectors they are not necessarily so. By the same token shell collectors can run the gamut of the occasional beach comber picking up shells on the sea shore to serious collectors who delve into serious study of sea shells. For myself I would consider myself to be an amateur conchologist. I love sea shells, the collecting of them, studying their variations, and learning their scientific classifications, geographic distribution and the minutiae of related information pertaining to sea shells.
   Seashells are divided into four molluscan orders: the gastropods (snails such as conchs), bivalves (such as clams), polyplacophora (chitons) and scaphopoda (tusk shells). In addition conchologists also study a subclass of Cephalopods called Nautiloidea (the most familiar of which is the Nautilus).
Examples of (clockwise from left) bivalves (Angel Wing Clam),
polyplacophora (chiton), cephalopod (Chambered Nautilus,
live scaphopoda (tusk shells)
  There truly is no place on earth where shells cannot be found, be it inland or the sea. From waterways, streams, and lakes, even fossilized shells found in arid deserts or on mountains to the beaches and depths of the seas.