GEOLOGY AND PALEONTOLOGY. 25 
was organized in independent parties, each chief of party reporting 
to the Director; and (4) from 1900 to the present, during which the 
geologic and paleontologic work has been in a single administrative 
division, but separated for scientific supervision into several sections. 
(1) The law of 1879, under which the Survey was organized, defined 
the duties of the organization as the ''classification of the public lands 
and examination of the geological structure, mineral resources, and 
products of the national domain." Under this law, as interpreted by 
the first Director, the activities of the Survey were confined entirely 
to the public lands, and consequently to the Western States. The 
work was organized under five divisions, each of which was practically 
complete in itself, carrying on geologic, topographic, and chemical 
investigations. This form of organization continued for two years, 
when topographic work independent of the geologic parties was 
begun. Shortly afterwards the same action was taken with regard 
to paleontology, and at the same time a separate division was formed 
for the collection of statistics of mineral production. At the end of 
this first period, therefore, the work of the Geological Survey had 
become well differentiated and most of the forms of activity in which 
it is at present engaged were represented. In 1882 an amendment to 
the sundry civil bill was passed providing for the preparation of a 
geologic map of the United States, and this was regarded as sanction 
for extending the work of the Survey over the whole country. New 
divisions were therefore established for the investigation of the eastern 
portion of the United States as well as the western. 
(2) During the second period the work of the Survey was divided 
into three groups of divisions — geologic, geographic, and accessory. 
Under geologic were grouped the following divisions: 
1. Division of Archean geology. 
2. Division of Atlantic Coastal Plain geology. 
3. Appalachian division. 
4. Lake Superior division. 
5. Division of glacial geology. 
6. Montana division. 
7. Yellowstone National Park division. 
8. Colorado division. 
9. California division. 
10. Division of volcanic geology. 
11. Mississippi division. 
12. Potomac division. 
Paleontology was also divided into the following divisions: 
1. Division of vertebrate paleontology. 
2. Division of Paleozoic invertebrate paleontology. 
3. Division of Mesozoic invertebrate paleontology. 
4. Division of Cenozoic invertebrate paleontology. 
5. Division of paleobotany. 
6. Division of fossil insects. 
