crinoid.art

October 28th, 2005

INTRODUCING CRINOID PARTS

Most
of a crinoid’s body, in fact usually at least 80% or so, consists of a
skeleton of calcium carbonate pieces, or ossicles, held together
by ligaments and muscles. This skeleton explains both why crinoids make
good fossils (calcium carbonate is basically limestone) and why not too
many creatures subsist on a crinoid diet (they’re highly crunchy). It also
forms the basis for crinoid classification. Fortunately for taxonomists
around the world, this skeleton is usually covered only with a thin epidermis
(and is thus an endoskeleton) and is clearly visible although you generally
need a dissecting microscope to see many diagnostic features. With few
exceptions, crinoid soft parts are not especially important in classification,
but this is probably because they’re a pain to deal with and few people
have bothered. We’ll discuss visceral matters later.

The crinoid body consists of three basic parts. A segmented stalk
(1) supports a cuplike calyx or aboral cup (2), which contains
or supports the viscera and from which radiate five segmented and usually
branched rays (3). Stalks consist of a series of ossicles called

columnals held together by ligaments, plus a variety of holdfast
structures. Sea lilies retain a stalk throughout their lives. Comatulids
develop a stalk following a larval stage, but shed all but the topmost
segment to take up a free-living existence as juveniles.

samhain.art

October 28th, 2005

Strange Horizons Fiction: The Great Old Pumpkin, by John Aegard

As you are no doubt aware, I am the issue of solid Dutch stock—the prosperous Van Pelt family of St. Paul. Mine was a comfortable and happy childhood, and I spent much of it in the devoted service of the Great Old Pumpkin. For him, I cultivated an annual pumpkin patch—mostly Autumn Gold and Big Max, as I thought he would find the Atlantic Giants tacky. I also evangelized him in the community, relating the tale of how, every year on Hallowmas Eve, the day when the spiritual most strongly encroaches on the substantial, this mightiest of gourds would rise to revel across the world with the most sincere of his adorers. My neighbors were understandably skeptical; after all, not once had this superbeing ever chosen to grace my pumpkin patch or any other place in our town. I vowed that I would coax him into my backyard, and I set out in the manner of a learned man to discover how I might do this.

Props to BoingBoing who pointed this out several times.

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