204 The American Geologist. March, 1891 
would be stored all the available information touching every economic 
interest that can be thought to belong to the geology of the state. 
Of the scientific character and merits of the body of the work we can- 
not here speak with such assurance and thoroughness as we would like. 
The authors are mostly well-known geologists, and it is only necessary 
to mention their names to gain the attention of all who are interested in 
such scientific work. Mr. Ulrieh bears the largest burden of this author- 
ship. Besides adding a large number of new forms to the Spongiye, he 
has given a sketch of their structural peculiarities, geological distribu- 
tion and their classification. In joint authorship with Dr. O. Everett a 
very rich sponge-bearing stratum of the Trenton formation is worked 
out. The specimens were collected by Dr. Everett three miles north- 
west from Dixon, 111., and are divided among three orders and ten genera. 
They are found in a shaly layer or a "mud stratum," between heavy 
layers of limestone, about twenty-five feet above the top of the St. Peter 
sandstone. 
The bryozoa, however, which occupy more than one-half of the body 
of the book, are treated in great detail and fullness. This part of the 
volume cannot fail to be considered by paleontologists, for many years 
to come, one of the chief authorities on bryozoa. Mr. Ulrieh has been 
•criticised, but generally by those who but partly understood his views 
and classification and, of course, always by those who had not seen this 
presentation of them. For this reason the delay in this volume has been 
unfortunate for Mr. Ulrieh. Here will be found Mr. Ulrich's classifica- 
tion, and its reasons, presented inextemo. The memoir does not abound 
in references to cotemporary literature. We notice two figures, one on 
p. 401, and one on p. 643, which have before appeared in the Geologist, 
but there is no acknowledgment of that fact, nor of the earlier publica- 
tion of the new species which they illustrate. 
Mr. Worthen, besides chapters on the drift deposits and on the 
economic geology of the state, contributed a description of fossil in- 
vertebrates, and the crinoids and blastoids are treated by Messrs. 
Wachsmuth and Springer. 
The appendix, which is illustrated by a portrait of Prof. Worthen, is 
by N. W. Bliss and Charles A. White, and gives a sketch of Prof. 
Worthen's life and scientific work. 
First Annual Report of the Geological Survey of Ohio (Third Organ 
ization ), by Edwakd Orton, State Geologist. Royal octavo, 323 pages, 
maps in separate envelope, Columbus, Ohio, 1890. 
This report is issued uniform in style of binding and size of pages 
with the final volumes of the survey which preceded it. The report for 
1889 is exclusively devoted to a description and consideration of the 
marvellous natural gas and oil wells which have been developed in Ohio 
and Indiana within the last five years. The various questions, of the 
origin of natural gas and petroleum ; the explanation of the pressure 
under which the gas rushes forth when the drill penetrates the reservoir 
