c6 The American Geologist. July, lotici 
compared to it is the Coal Flora, by Lesquereux, published by the 
Pennsylvania survey. To students and collectors of coal plants, es- 
pecially in the Lower Measures, this book is invaluable, and it is a 
much needed example in methods of collection, study and publication. 
It will make clear the fact that little can be done in satisfactory classi- 
fication and discussion of a Carboniferous flora without a great body of 
material for comparison, and without recourse to a very extensive lit- 
erature. However discouraging this may be to many students, it is 
nevertheless true. The United States National Museum has already be- 
come the great depository of coal plant material in this country, and, 
with its great number of American types, will doubtless remain a cen- 
ter of systematic work in this field. The experience, the knowledge of 
the plants and the paleontological ability shown in this volume place 
its author in the lead among American students of Paleozoic plants. 
Whoever has attempted the determination of Carboniferous plant 
species with no other aid than the earlier memoirs on the younger 
Paleozoic floras realizes the insufficiency of a great part of the descrip- 
tions and the lack of data as to the localities or horizons of the fossils. 
A large proportion of the collections of the past, even those which 
formed the basis of the writings of Lesquereux, were so incomplete, so 
carelessly collected, their stratigraphical origin so generalized or in- 
definite, that they are largely valueless for correlation. What is im- 
peratively needed is full collections of plant remains from exactly 
known horizons, and over wide areas. There remains plenty of work 
of the right kind to be done. 
The book consists of ^t^ quarto plates, nearly all of them being 
photographic reproductions of plant remains, and 307 pages of quarto 
text. The first ten pages are given to introductory description of the 
collection and localities; the last 2)2 pages are general discussion of the 
geological significance of the flora and its correlation, while the rest 
of the book, 265 pages, is detailed description of the species. This bio- 
logical portion of the work is admirable in its fullness, refinement and 
lucidity. The full bibliography and synonymy are evidence of the de- 
tail and difficulty of the study and of the scholarship of the author. 
Nearly all of the plant material is from Henry county, Missouri, 
large in amount and covering many years of collecting, thus repre- 
senting fairly the plant life of the coal basin. 
Dr. J. H. Britts of Clinton, Mo., collected the larger part of the 
material, which was mostly derived from two horizons about 45 feet 
apart, and separated from the old Mississippian (Lower Carbonif- 
erous) land surface by less than 100 feet of sediments. The flora is 
"representative of that division of the Carboniferous resting on the 
Pottsville series in the northern and northeastern coal fields." 
The species described, number 123, representing nearly all the 
common genera of the middle Carboniferous of Europe and America. 
They are distributed as follows: Algfe, 2; Fungi. 2: Ferns. 70; Eqitiseta 
19; Lepidodendrids, 12; Sigillarids, 2; Taeniophyllids, 2; Gymnosperms. 
10. The author draws attention to the preponderance of ferns, es- 
