Geology and Mineralogy. . 151 
Paleozoic fossils of Pennsylvania would throw much light on the 
actual distribution of the species so well studied by Professor 
Hall in New York; and it is not at all improbable that com- 
mingling should exist of fossils that are confined in New Yor 
distinct horizons, proving changes from migrations like those 
gested by rules or conclusions regarded as “established” may 
Beyond the fact that the observations make 
¢areful geological observers on the survey. 
- Pas Antlitz der Erde, yon Epuarp Suzss, mit Abbildungen 
und Kartenskizzen. Erste Abtheilung, 310 pp. large 8vo. 1883. 
Prag (F. Tempsky) and Leipzig (G. Freytag).—The present vol- 
ume forms the first of three parts of which it is announced that 
the complete work will consist. The whole subject, after the 
introduction, is to be discussed under four heads, entitled—(1 The 
he preceding statements, taken from the prospectus, will 
sir the scope of the work, as it is to be finally completed. Th 
volu 
division of the subject as above defined. The author opens the 
~? 
