SCIENTIFIC LITERATURE. 



zy7 



tion in 1896 was guided by the consideration 

 of bringing to the attention of the public 

 geological deposits of great importance, and 

 of choosing such locations as would eluci- 

 date as large a number of geological prob- 

 lems as possible. Six counties are described 

 and mapped as geologically important in re- 

 spect to indui'ated rocks and superficial de- 

 posits, and as being, therefore, of great 

 practical interest to the people of the State. 

 The soils are treated as economically the 

 most important formations. Tests of build- 

 ing stones have been completed and are 

 ready for publication. Attention correspond- 

 ing to their importance was given to the 

 study of the coal beds. It was incidentally 

 demonstrated that the succession of Pleis- 

 tocene deposits is more complete and more 

 clearly indicated in Iowa than in any other 

 corresponding area of this continent so far 

 studied. The State Geologist is gratified to 

 represent that the publications of the survey 

 are being more and more appreciated, and 

 are received by the people of the State as 

 well as by men of science everywhere with 

 increasing favor. Requests for copies of the 

 reports are very numerous and indicate a 

 widespread interest. High schools in coun- 

 ties already reported upon have introduced 

 the separate county reports as works to be 

 read by the pupils studying geology, and 

 newspapers publish summaries of reports of 

 local interest. 



The object of Prof. L. H. Bailcy''s Lessons 

 with Plants * is well indicated by its second- 

 ary title ; it is to suggest methods of Nature 

 study; not to teach a science, but only to 

 indicate a way in which plants may be stud- 

 ied and the subject taught. The lessons are 

 an extension of the ideas embodied in the 

 Nature Study Leaflets issued for the use of 

 teachers by the College of Agriculture of 

 Cornell University; while these leaflets are, 

 in turn, the direct growth of "observation 

 lessons " which were a part of the instruc- 

 tion given in itinerant schools of horticulture 

 in the State of New York. When the book 

 is used by the teacher, he is supposed to 



* Lessons with Plants. Suggestions for See- 

 ing and Interpreting some of the Common Forms 

 of Vegetation. By L. H. Bailey, with Delineations 

 from Nature by W. 8. Ilaldsworth. New York : 

 The Macmillan Company. Pp. 491. Price, $1.10. 



master an observation, collect specimens 

 proving or illustrating it, and teach his pu- 

 pils from the specimens. If the pupil con- 

 sults it, he collects specimens and recites 

 from them, not from the book. Pupils will 

 not do this so well by themselves as when 

 under the inspiration of the teacher; for 

 while it is not true that only those things are 

 useful which one finds out for himself — else 

 we could make little progress — "the pupil 

 should find out something for himself, and, 

 more than all, he should enjoy the finding of 

 it." The lessons teach and picture what are 

 to be found in twigs and buds, leaves and 

 fohage, flowers, fruits, the propagation, be- 

 havior, and habits, and the kinds of plants ; 

 while the appendix contains suggestions on 

 pedagogical methods, books, classification, 

 evolution, the interpretation of Nature, the 

 growing of plants, and a glossary. 



Mr. Edward P. Thompson's narrative of 

 the exploration of the Cave of Loltun, near 

 Labna, Yucatan, in 1890-'91, is given as 

 No. 2, Volume I, of the Memoirs of the 

 Peabody Museum of American Archaeology 

 and Ethnology of Harvard University. The 

 cave was excavated through all the deposits 

 that had been made in it " down to and into 

 the crystalline surface of the ancient floor 

 itself." Numerous interesting remains of 

 man and human life were found, inscriptions 

 and specimens of art, but nothing indicative 

 of primitive savagery. Typical examples of 

 these relics are represented in figures in the 

 text and in large photographic plates. 



D. T. Day^s twelfth Report on the Min- 

 eral Resources of the United States (1895) ap- 

 pears in a somewhat different form from the 

 previous reports, the pages being enlarged, 

 and is pubhshed in two volumes as Part III 

 of the seventeenth annual report of the Geo- 

 logical Survey. In it the scope has been lim- 

 ited more than in previous reports to the sta- 

 tistics of production of the minerals and 

 statements of the conditions of their occur- 

 rence, and less space has been devoted to the 

 technical features of their development. 



From the United States Geological Sur- 

 vey we have the monographs from the twen- 

 ty-fifth to the twenty-eighth volume, inclusive. 

 The twenty-fifth volume comprises the sur- 

 vey of the former bed of the very large Lake 

 Affassiz, which occupied the Red River Val- 



