nd the
organization by which it is to be made. Mr. Henry Gannett is the Chief
Geographer.

PALEONTOLOGY.

Before giving the outline of the plan for the general geologic survey, it
will be better to explain the accessory plans and organizations. There are
in the Survey, as at present organized, the following paleontologic
laboratories:

1. A laboratory of vertebrate paleontology for formations other than the
Quaternary. In connection with this laboratory there is a corps of
paleontologists. Professor O.C. Marsh is in charge.

2. There is a laboratory of invertebrate paleontology of Quaternary age,
with a corps of paleontologists, Mr. Wm. H. Dall being in charge.

3. There is a laboratory of invertebrate paleontology of Cenozoic and
Mesozoic age, with a corps of paleontologists. Dr. C.A. White is in
charge.

4. There is a laboratory of invertebrate paleontology of Paleozoic age,
with a corps of paleontologists. Mr. C.D. Walcott is in charge.

5. There is a laboratory of fossil botany, with a corps of paleobotanists,
Mr. Lester F. Ward being in charge.

The paleontologists and paleobotanists connected with the laboratories
above described, study and discuss in reports the fossils collected by the
general geologists in the field. They also supplement the work of the
field geologists by making special collections in important districts and
at critical horizons; but the paleontologists are not held responsible for
areal and structural geology on the one hand, and the geologists are not
held responsible for paleontology on the other hand. In addition to the
large number of paleontologists on the regular work of the Geological
Survey, as above described, several paleontologists are engaged from time
to time to make special studies.

CHEMISTRY.

There is a chemic laboratory attached to the Survey, with a large corps of
chemists engaged in a great variety of researches relating to the
constitution of waters, minerals, ores, and rocks. A part of the work of
this corps is to study the methods of metamorphism and the paragenesis of
minerals, and in this connection the chemists do work in the field; but to
a large extent they are occupied with the study of the materials collected
by the field geologists. Professor F.W. Clarke is in charge of this
department.

PHYSICAL RESEARCHES.

There is a physical laboratory in the Survey, with a small corps of men
engaged in certain physical researches of prime importance to