DEPARTMENT OF THE INTERIOR

UNITED STATES GEOLOGICAL SURVEY

DIVISION OF VERTEBRATE PALEONTOLOGY

NEW HAVEN, CONN.

October 8, 1897.

Robert Butler, Esq.

Dear Sir!

I have your letter of the 1st inst., and am much interested in what you write about the animal you have discovered, and write at once in reply.

I have a great number of Dinosaurs from your region, and can use
still more if they are different from those I have, as I am now engaged
in writing a large volume about this group of reptiles.

I cannot make out from your brief description what the animal is,
but could probably decide at once from a single tooth, or vertebra, or
foot-bone. You do not mention the exact locality, but I think you will
find the formation to be Laramie instead of Eocene, and the animal may
perhaps be *Claosaurus*, as that is the most abundant Dinosaur in your
region.

Meanwhile, I send you my last book on " North American Dinosaurs,"
and from the plates and figures, you will doubtless be able to make out
what you have found. On Plate LXXIV, you will find a restoration of
*Claosaurus* from the Laramie, and on Plate LXXVIII, you will find the
teeth of several Dinosaurs figured, which may help you out.

I enclose herewith some franks which will enable you to send me
free, by mail, two or three characteristic bones, so that I could make
out just what the beast is. Each frank will cover several pounds, if
sent well packed in a tin can.

If the head and other portions are in a very soft sandstone, the bones, also, will be soft, and it is important not to try to get them out of the rock. They can be hardened by a solution of gum arabic, or, better still, by covering the exposed parts with plaster. Of course, every fragment should be carefully saved. The value of the specimen will depend (1) on what it is, whether new or not; (2) how well preserved the bones are; and (3) what part of the whole skeleton, including the limbs, can be secured. On these points, I could not judge before seeing at least some of the important parts of the skeleton.

Are any of the legs or feet in position, especially the fore feet?
How far is the locality from the railroad?

Hoping soon to hear from you,

Yours, truly,

(Signed) O. C. Marsh.

2

between us I am sure we can do better by you than anyone else, and also
take what you get later.

One thing is very important. The specimen should be very carefully
boxed in separate, *tight*, strong boxes, and these numbered. The skull
in a box by itself ( No. 1 ) so packed with braces that it cannot move.
A crate will not answer, as if it moves the small pieces will fall out.
The neck in Box 2, etc. The pieces of supposed skin are important, and
could be very carefully packed in a box by themselves, so that they cannot
rub or touch each other. A diagram showing just how the skeleton lay,
and how the sections are related to each other, is important.

I sent the book to Mr. Hopkins, as you requested, and another paper
to yourself that you will find useful. Will send you some others soon,
and also will write more fully.

Yours, truly,

( Signed ) O. C. Marsh.