Eeoieiv of Recent Geological Literature. 51 
many sections and maps, with tables of their production in the various 
countries, together with a very bri^f history of their exploitation in those 
countries. In a somewhat extended discussion the physical conditions 
under which the different coals were formed are considered, as well as 
some of the problems as to the age of the eastern and southern coals. 
The latter he regards as of true Carboniferous age, the change in the plant 
life from a palteozoic to a mesozoic facies being credited to a change of 
climate caused probab'y by glaciation, occurring in the latter half of the 
Carboniferous epoch. The synopses of the great families of the coal 
plants, desci'ibed in un-technical language, with brief characterizations of 
many of the principal genera and species, is a feature of the work which 
geologists in the field will duly appreciate in such a hand book. In the 
systematic classilication of the coal flora the author proves himself fa- 
miliar with the work of the leading European authorities on palajozoic 
plants, and he adapts it to the mofrt recent results obtained by Stur, Weiss, 
Williamson, Renault and Grand Eury in the course of their pala^obotani- 
cal investigations. This is illustrated by six quadruple plates of the most 
widely distributed coal plants, engraved with unusual excellence, and 
giving special prominence to the nervation and detail. The form con- 
venient for the pocket, in which the book is published, suggests the 
utility of an English translation in a similar edition. 
Notes on tJie geology of western Texas. By Prof. Robert T. Hrr.c, 
(Reprint from the Texas Geological and Scientific Bulletin; Austin, Oct., 
1888.) Professor Hill reports on two trips made by him over "the vast 
prairie and mountainous areas of western Texas which seem to be the 
geological terra incognita of the United States." Along the line of the 
Texas Pacific Railway he finds a rich field "for competent scientific inves- 
tigators." Equally important was the trip from Texarkana westward to- 
Henrietta, and thence north-west over the plains and up the valley of the 
Canadian to Tucumcarri mountain in New Mexico. "The surface of the 
Llano Estacado," he saj's, "is an early ((uaternary loam, and a direct con- 
tinuation of the great plains of Kansas and Nebraska, while the white- 
matrixed conglomerate which appears so clearly as the surface of the 
valley dividing the north and south plains is a later quaternary deposit. 
This all implies: ^rs?, a great basin of aqueous sedimentation in early 
quaternary time of the region now occupied by the Llano Estacado; 
Second, a subseciuent elevation to a hight, but in no way approaching its 
j)resent altitude; Third, a subsequent semi-submergence, during which 
time the sediments (tierra blanca of the Mexicans) of the trans-Pecos 
mountain valleys, and of the wonderful sub-plains or valleys now occu- 
pied by the Pecos, Rio Grande and Canadian were cut ; fourth, a later, 
rapid and enormous uplifting of the region to the present altitude, the 
course of which is recorded in the extrusions of eruptive masses of 
'malapais' or recent volcanic rocks. In fact these plains, and the geology 
of the whole region bring to the eastward many miles our knowledge of 
the wonderful phenomena of Mount Taylor and the Zuni plateau, west of 
the upper Rio Grande, and give us the connecting link between the 
