THE COAL MEASURES AMPHIBIA
OF
NORTH AMERICA
By
ROY LEE MOODIE
Associate in Anatomy, University of Illinois, Chicago
Published by the Carnegie Institution of Washington
WASHINGTON, 1916
CARNEGIE INSTITUTION OF WASHINGTON
Publication No. 238
PRESS OF J. B. LIPPINCOTT COMPANY
PHILADELPHIA
PREFATORY NOTE.
The Carnegie Institution of Washington has already published several monographsupon paleobiological subjects, written by its research associates, Hay,Wieland, and Case. Each author has dealt with the subject-matter of his particularfield, but each has brought to bear upon his work common factors which haveplaced his labors upon a broader basis than the mere morphological descriptionsof fossil forms of life. Case has published four monographs upon the morphologyand taxonomy of the Permo-Carboniferous vertebrates of North America, andhas followed these by a fifth, in which all the known factors bearing upon thedevelopment of the life were assembled in an effort to discuss the paleogeographyof the period. In his conception paleogeography is a very broad term, involvingnot only a study of the distribution of land, water, and life in any one interval oftime, but a consideration of all the factors in the extremely complex inter-relationsof organic and inorganic matter and causes which influence the developmentof each part.
Geologists and paleobiologists have alike suffered in their interpretation ofpast conditions, because of their lack of knowledge of the work done by others.Stratigraphy may not be interpreted from the preserved fossils without a knowledgeof biological laws, and the formations of the earth may not safely be rearrangedto account for the present or past distribution of life without a knowledge of geologicalprocesses.
It is obvious that such work is beyond the possibilities of any one man; it israther the work of a group of men, each broadly trained and each master of hisown field and able to contribute to and criticize the work of his fellows. Nowherecould close cooperation of this kind be better accomplished than under a systemsuch as the Carnegie Institution of Washington has developed, whereby the researchassociates of the Institution and others of its staff may call in the assistance ofmen in related fields. Already the value of this procedure is apparent in the resultsaccomplished by cooperation.
The following monograph, by Dr. Roy L. Moodie, adds an important link tothe series of paleobiological publications of the Institution and is closely connectedwith the work already done upon the Permo-Carboniferous vertebrates, since itsupplies a description of the life of the period immediately preceding. It is hopedthat the volume will contribute in no small measure to an understanding of thebroader problems of paleogeography and the recognition of the mutual problemsof the paleobiologi