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RE: Addendum to UPDATE (Maryland tracks)

        -----Original Message-----
        From:   RAY D STANFORD [SMTP:STARSONG@prodigy.net]
        Sent:   Monday, February 22, 1999 9:25 PM
        To:     Stewart, Dwight; Dino mailing list
        Subject:        Re: Addendum to UPDATE (Maryland tracks)

        Hello Dwight and List,

            Dwight, your question is an important one:

            QUESTION:  Is there evidence for a digit 1CLAW in the Sauropod

            ANSWER:  In FOUR of the fourteen (I just counted them.) Sauropod
        tracks from the Cretaceous (possibly Aptian -- Tom Lipka is working
        dating) of Maryland, one sees impressions that might be interpreted
        evidence of a rather small claw associated with digit 1.  These
marks could
        not have been made by a really big claw, but I get the impression
(It would
        be nice to have more examples to study.) that its angle of
orientation might
        have been somewhat variable:  slight,  within horizontal plane of
the manus,
        but maybe more-so,  within a vertical direction as well.  Certainly
        (if that is what the referenced depressions represent) would not
have made
        much of a defensive weapon, so maybe it had some other function.

           I was theorizing more along the line of a digging function.  Were
sauropod eggs
        laid in furrows or do we know that yet?


            The relative size of the digit 1 claw might be similar to the
        small one carried by Brachiosaurus brancai, as shown in a skeletal
        illustration in Figure 42.8 -G, on page 379 of the book DINOSAUR
        TRACES (pages 371 through 393, being a chapter entitled Brontopodus
        Lower Cretaceous Sauropod Footprints from the U.S. Gulf Coastal
Plain, by
        Farlow, Pittman, and Hawthorne), Cambridge University Press, 1989.

            Greg Paul's illustration, published in at least two different
books, of
        adult Astrodon johnstoni with young is probably quite accurate, if
        reasonably accepts the Maryland imprints we have found as having
been made
        by that animal.

            In one of the best Sauropod manus imprints from Maryland, we see
a small
        but very distinct, 'trench'  ("V"-shaped in cross section) that
might have
        been produced by a digit 1 claw scraping inward (posterio-medially)
as the
        manus was lifted from the substrate.

            I think we can be reasonably sure of the most obvious of the
        Sauropod manus features, simple because they are so precisely
replicated in
        a good variety of substrate types, and across a nice range of sizes.

            The largest Sauropod manus imprint yet found here (I am aware
only of
        those in my collection.) is 35 cm across at its broadest expanse.
        smallest is only 4.5 cm across!  Yet, these two and those in between
        size) are consistently and impressively similar.

            Thanks for that good question, Dwight.  I know 'trackers' other
        myself have been looking for digit 1 manus claw impressions, but an
not sure
        whether I've read of similar impressions being found elsewhere.
        have the answer to that?

            Ray Stanford

        I was wondering about the Glen Rose site here in Texas.  I've
visited the site
        (only it was years ago) & have seen pictures of the trackway, but
don't recall any
        mention of claw indentures one way or the other.