Re: Mesozoic burrows?

["Ray Stanford" <dinotracker@earthlink.net>]

    John Bois asked, "Are there any burrows known from the Mesozoic--burrows
from small to middle size mammals?"

    I have recovered six burrows from the Early Cretaceous of Maryland,
right in your 'stomping ground', John. They are not the long, beautifully
spiraled type I have seen at the Smithsonian's NMNH, however.  Each is
hollow, with walls more consolidated (and by whatever means tougher) than
the matrix.  The longest I have found is only about 20 cm.  In most cases
there is a wider, oval opening that tapers into the burrow.  In a different
type, there is a small opening of about 18 mm diameter, but this opens into
a rather remarkable chamber of about the volume of a medium to large
grapefruit.

    Having no well-informed idea of what kind of animals made the burrows,
crayfish and large, burrowing insects come to mind.

    Another interesting burrow-shaped find from the Early Cretaceous of
Maryland in just under 8 cm long, with a wall thickness of roughly 17 mm,
and with its internal cylindrical hollow being roughly 4 cm in diameter.  It
was constructed by mud-cementing what seem to have been small sticks.  While
the several dinosaur paleontologists who have seen it have been puzzled as
to its maker, a well-informed geologist/naturalist friend assures me that it
is a fossilized "crayfish tower".  It is in great shape, and if the friend
is right, I suspect it may be a rather rare fossil find, for the Late
Cretaceous.

    These may not be the kind of burrows you had in mind, John,  but I
thought I should mention them.
Ray Stanford

"You know my method.  It is founded upon the observance of trifles." --
Sherlock Holmes in The Boscombe Valley Mystery

----- Original Message -----
From: "John Bois" <jbois@umd5.umd.edu>
To: <dinosaur@usc.edu>
Sent: Sunday, July 29, 2001 10:09 PM
Subject: Mesozoic burrows?


I saw a beautiful Miocene burrow at the Smithsonian
and thought it strange that I've never read of one from the Mesozoic.