hesfeet.jpg (112792 bytes)

Williston, S.W. 1896.

On the dermal covering of Hesperornis.


Kansas University Quarterly 5(1):53-54, pl. II.

 

Copyright 2009-2010 by Mike Everhart

Page created 01/15/2009 - Last updated 03/09/2010

Wherein S.W. Williston describes scales covering the lower legs of Hesperornis and associated feathers from a specimen collected in 1894 in Graham County by H.T. Martin..


 

On the Dermal Covering of Hesperornis.

--------------

BY   S.  W. Williston

--------------

(With Plate II.)

     A specimen of Hesperornis, collected in western Kansas the past
year by Mr. H. T. Martin and now in the University Museum, is
of especial interest from the information it affords of the dermal
covering of this Cretaceous toothed bird.
     The specimen, which is in excellent preservation, lies upon a
chalk slab, with the head doubled partially under the pelvis.  Some
six or eight vertebrae, together with the humeri and coracoids and
many of the ribs are wanting; otherwise the specimen seems
perfect.  The size is distinctly less than that of H. regalis, and
it does not seem to be due to immaturity.  Possibly the species is
identical with H. gracilis, which has been only imperfectly de-
scribed.
     The photographic illustration given in Plate II was taken from
the fragment removed from the slab over the right tarso-metatarsal,
the surface of the slab itself being less clearly, though more fully
marked.   I have sketched in the bone to show the relative size and
position
     The podotheca is seen to be scutellate in front.  The structure
is shown so clearly in the photography that I need not enter into a
fuller description.  The scutes are all smooth, not imbricated, and
distinctly separated from each other.  The are a little longer from
side to side below, though not much.    I count twenty-six on
the slab, and to the back part of the bone, while impressions of
the feathers will be seen on the opposite side
     These feathers were evidently long, reaching nearly to the
phalangeal articulation,  and are clearly semiplumulaceous in
character, the pennaceous shaft of considerable size, the vanes
long and wavy.   The shaft of one feather is seen in the illustration
lying close to the outline of the bone, and is of considerable size.
I doubt not that the feathers throughout were of this character, or
wholly plumulaceous.  I find distinct impressions of the wavy
vanes at the back of the head and elsewhere, but in no case is
there the impression of a true feather, as I think would surely be
the case had the bird possessed them.
                                 
(53 KAN. UNIV. QUAR., VOL V, NO. 1 JULY 1896,

54                                                           Kansas University Quarterly,

     This plumulaceous character of the plumage is not unexpected.
Although Marsh nowhere mentions the plumage in his work, I
know that he personally had the opinion that it was of a downy
character.  That the feathers of the tarsus should extend to the feet
in a wading bird seems surprising, but there can be no other
interpretation of the specimen.

 

 

 

 

 

Kan. Univ. Quar., Vol. V.                                                            Plate II

 

Williston1896Pl2.jpg (59100 bytes)

 

Dermal Covering of Hesperornis
Enlarged about one-fourth