876 



SCIENCE. 



[N. S. Vol. III. No. 76. 



ferred Brongniart's nomen nudum Mantellia nidi- 

 formis to Buckland's Cycadeoidea megalophylla, 

 although the latter was thoroughly described 

 and illustrated and also had priority, as he, 

 himself, admits. In the example before us the 

 last author named is, of course, responsible for 

 referring Bennettites to Cycadeoidea, which, 

 whether correct or not, was a legitimate change 

 and the reasons were given in the paper re- 

 ferred to. 



These three cases will sufBce to furnish the 

 standard by which the whole is to be judged, 

 and it is obvious that the system of citation 

 adopted in this work, which is simply repre- 

 sentative of the whole class of writers referred 

 to, and for which its author should not be held 

 personally responsible, involves both the sup- 

 pressio veri and the suggestio falsi. That this 

 should be tolerated in any department of 

 science, the essence of which is truth, is surely 

 beyond the ordinary comprehension. 



Lester F. "VVaed. 



Washington, D. C. 



A Summary Description of the Geology of Penn- 

 sylvania. J. P. Lesley, Harrisburg. Vols. 

 I. and II., 1892; Vol. III. in 2 parts, 1895. 

 pp. 2638 and 611 pi., with an index volume 

 of pp. 98 and xxx. 



These volumes, completing the series of Penn- 

 sylvania reports, are offered as a digest of about 

 one hundred volumes, averaging not far from 

 two hundred pages each. A review, even a 

 synopsis, is impossible; space admits merely of 

 a notice. 



Prof. Lesley's contribution covers the col- 

 umn from the base to the Mauch Chunk of 

 the Lower Carboniferous ; failing health com- 

 pelled cessation of work at that point, and the 

 compilation had to be completed by others. 

 The portion described by Prof Lesley is 

 found in the most complicated part of the State, 

 and the problems with which he had to deal 

 were numerous and perplexing. The conclu- 

 sions offered by geologists in adjoining districts 

 were often discordant, and the termination of 

 the survey came too soon to admit of careful 

 re-study of doubtful areas. As a result, the 

 first two volumes of this report contain many 

 defective spots, which the author does not at- 



tempt to conceal. The Cambrian and Ordovi- 

 ciari, studied chiefly during the early years of 

 the survey, need thorough revision, and the re- 

 lations of the Pennsylvania Silurian to that of 

 other States are still somewhat obscure. The 

 discussion of the Devonian is careful and as ac- 

 ceptable as any discussion of the Pennsylvania 

 Devonian can be at this time. The numerous 

 deep oil borings in southwest Pennsylvania 

 and West Virginia will afford new material 

 for study of the problems involved. Prof. 

 Lesley's industry is simply appalling ; he has 

 mastered the details of the reports in such way 

 as to make them his own, and his portion of 

 these volumes bears his own stamp on every 

 page, so that we have not a mere compilation 

 but a real presentation of the geology as far as 

 the condition of our knowledge warrants. His 

 anxiety to escape the ' error ' of the director of 

 the First Geological Survey of the State is 

 shown in the effort to fasten every geologist's 

 name to his work, even, at times, to the extent 

 of crediting to the geologist in charge of a dis- 

 trict observations which were only confirmatory 

 of his own made many years before. His read- 

 iness to give a hearing to both sides is evi- 

 denced not merely by the insertion of an argu- 

 ment, by another, of thirty pages contro- 

 verting a position strenuously defended by him 

 for more than twelve years, but also by his rel- 

 egation to the doubtful column of opinions 

 long regarded bj' him as proved. 



The Mauch Chunk west from the Anthracite 

 fields and the Pottsville conglomerate through- 

 out the State are described by Mr. d'lnvilliers 

 in Vol. 3, pp. 1833-1915. The synopsis of the 

 labors of Prof White and others is given 

 clearly and compactly and with a reasonable 

 effort to assign to each author proper credit ' 

 for his work. 



The Anthracite fields are described by Mr. 

 A. D. W. Smith on pp. 1916-2152 ; this sum- 

 mary appears to be in large part supplementary 

 to the reports and work of Messrs. Ashburner 

 and Hill. 



The Bituminous coal fields are described by 

 Mr. E. V. d'lnvilliers, on pp. 2153-2588, 

 this description forming the greater part of 

 Vol. III., Pt. I. Mr. d'Invillier's work has 

 been conscientious and successful, so that his 



