Re: Fwd: paleonet Endocerid size

[Roy Plotnick <plotnick@xxxxxxx>]

At 09:46 PM 9/20/2004 -0400, you wrote:

I recall reading the following paper by Teichert & Kummel, although the
illustrated specimen was certainly not 9 meters.  Maybe they inferred that
endocerids would get to be that large, or someone else used their paper to reach that
conclusion.

"Size of Endoceroid Cephalopods", by Curt Teichert and Bernhard Kummel. 
Breviora, 128 (1960).

Thanks Alan. I have now had a chance to read over this paper. The relevant specimen, illustrated in the article, is at the MCZ and is about 3 m long (I thank Fred Collier for calling and confirming this measurement).   It is not complete at either end.  Based on the dimensions of the specimen, Teichert and Kummel estimated that "the entire fossil from the preserved adoral end to the apex may have measured about 5,800 mm."  They argue that although they cannot find septa in the last 500 mm  that the entire specimen is the phragmacone.  They then add on an estimate of the length of the body chamber of 2,650 mm, assuming a ratio of about 1:0.5 of phragmacone to body chamber.  This produces a total length of about 8,450 mm (they say 8,150 - this may be a typo). 
So 8.5 m is their estimate of conch size, based on a 3 m specimen.  This approximate value is now enshrined in the Treatise (p. K160) and textbooks. Repeat at your own risk - Roy
 

Roy E. Plotnick
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