NOVEMBEB 21, 1913] 



SCIENCE 



743 



of a long promise and there need be no re- 

 serve in saying that the result is destined to 

 be of great value and durable service to geo- 

 logical science. 



Amid the diversified output of oiScial re- 

 ports on American geology there has been 

 nothing like this before — a monograph of a 

 single geological system and its component 

 faunas, wherein is given in detail all that is 

 known of the local development of the system 

 within definite, if artificial, boundaries. The 

 very expression of this fact, the realization 

 that here is a work of ultimate reference in this 

 field, brings with it the wish that other states 

 might have done like this for their own do- 

 main and to the great advantage of those who 

 seek to interpret the causes and sequences of 

 geology along the broader lines. Many ex- 

 pert men have participated in the creation of 

 this work; and here again, as so often, our 

 venerable adages break down, for many cooks 

 have neither spoiled the broth nor have many 

 hands made light work; for first, the collabo- 

 rators speak with reasonable finality, and 

 again, the conception of the state geologist 

 has labored long and hard, through many 

 years, to this successful parturition. 



The writer, having played a certain role in 

 the rendering of this composition, must re- 

 frain from any exuberant notice of it. Nor 

 would a critical review of the contents of the 

 work be appropriate to these columns. All in 

 due time the geological coroner with his hy- 

 potheses will be along to hold his inquest over 

 the corpus delicti. 



Volume 1 is devoted to the Lower Devonian, 

 volume 2 to the Middle and Upper Devonian, 

 and volume 3 consists of 165 plates, including 

 2,500-3,000 figures of fossils. The text 

 volumes are embellished with many half-tones 

 of geological scenery and accompanied by sec- 

 tion sheets in cover pockets, and volume 1 

 carries a map of Maryland with the Appala- 

 chian distribution of the Devonian members 

 accurately colored. 



The introductory chapter on the general 

 relations of the Devonian by Dr. Swartz 

 points out succinctly the correlation of the 

 formation in its various aspects, laying special 



emphasis on the discrimination of shore-line 

 and subcontinental deposits at the east from 

 contemporaneous marine deposits toward the 

 west, in correspondence with later Devonian 

 conditions northward in Appalachia. Pro- 

 fessor Schuchert has presented the paleogeog- 

 raphy of the Devonian with the aid of a 

 series of paleogeographic maps of North Amer- 

 ica, which illuminate the procession of geo- 

 graphical changes and are serviceable for dog- 

 matic purposes, even though recent blows of 

 the hammer have torn some cavernous rents 

 in them. 



Dr. Prosser contributes the Historical 

 Eeview and Bibliography. 



The lengthy chapter on the Lower Devonian 

 Deposits is the work of Messrs. Schuchert, 

 Swartz, Maynard and the late E. B. Rowe, 

 each responsible for a special section, Mr. 

 Schuchert for the general introduction, Messrs. 

 Swartz, Maynard and Eowe for the determina- 

 tive stratigraphy. Dr. Swartz for the forma- 

 tional correlation. All four have shared in the 

 " Local Sections," a chapter with which the 

 geological portion of the volume closes. 



In the descriptive paleontology which fol- 

 lows, the chapters and their authors are these: 

 Coelenterata, by Dr. Swartz; Cystidea, by 

 Professor Schuchert; Crinoidea and Vermes, 

 by D. W. Ohern; Bryozoa, by Drs. Ulrich and 

 Bassler; Brachiopoda, by Professor Schuchert 

 and Mr. Maynard; Mollusca and Trilobites, 

 by Messrs. Ohern and Maynard; Ostracoda, 

 by Drs. Ulrich and Bassler. 



Thus briefly are the contents of this vol- 

 ume 1 indicated, but only the stratigrapher 

 and paleontologist will appreciate the pene- 

 tration of these analytical studies. Perhaps 

 a leading feature of the stratigraphy is that 

 expressed by the authors of their conception 

 of the " Keyser member " of the series and 

 the discussion of its correlation value with 

 contemporaneous Appalachian deposits else- 

 where. This is a succession of homogeneous 

 limey sediments with a thickness of several 

 hundred feet which are assigned a place at 

 the base of the Devonian system. The de- 

 posits are continuous into Pennsylvania, but 

 their equivalents northward in New Jersey 



