SEriEMBEB 17, 1909] 



SCIENCE 



371 



etc., than with the Heterokontaj also included. 

 However interesting and important are the 

 speculations regarding the derivation of a 

 number of lines of green algae from a flagellate 

 ancestry, we have not as yet such knowledge 

 of the cytology of the reproductive cells as to 

 give a firm foundation for systems of classifi- 

 cation based chiefly or wholly on their struc- 

 ture. The groupings of the orders and fam- 

 ilies follow in the main well-knovm arrange- 

 ments and are easily understood. 



The introduction contains various matters 

 of interest, some of which might with advan- 

 tage have been grouped under headings and 

 perhaps given more extended treatment. 

 There are historical comments, remarks on 

 •distribution, several pages devoted to a very 

 practical description of methods of collecting 

 ■and preserving algse, references to literature 

 helpful to the general student, and at the end 

 the above-mentioned account of the system of 

 classification. 



As regards the form of the book, some sug- 

 gestions occur to the reviewer which are here 

 given with the thought that later editions will 

 te called for and also in the hope that Mr. 

 Collins will write similar synopses of other 

 groups of algse. Readers would greatly appre- 

 ciate page headings giving the genus on the 

 Tight-hand page and the family or order on 

 the left instead of the repeated title and pub- 

 lication. The figures would have been more 

 useful as illustrations if distributed as text 

 figures throughout the book, associated with 

 the genera that they illustrate, rather than 

 collected in a series of plates at the end. 

 These changes in form and arrangement, al- 

 though increasing somewhat the cost of pub- 

 lication, would be especially appropriate to a 

 taxonomic work and would certainly add to 

 the effectiveness of this remarkably clear and 



simple treatment. 



Bradley M. Davis 



Mandhooh for Field Geologists. By C. W. 



Hayes, Chief Geologist, U. S. Geological 



Survey. K^ew York, John Wiley & Sons. 



1909. 



It seems to be a trait of human nature not 

 i;o wish to buy official reports and to ignore 



the value of material contained in the same. 

 Advantage has been taken of this by certain 

 prudent publishers who reprint the more inter- 

 esting and widely important government re- 

 ports, finding a ready sale therefor. A num- 

 ber of Dr. Merrill's valuable books are prac- 

 tically reprints of guides to national museum 

 collections. The book before us is of this 

 class, and the publishers are to be thanked for 

 introducing so valuable a work to a wider 

 circle. This is practically a reprint of the 

 instructions to United States field geologists, 

 and any one who has occasion to do any prac- 

 tical work in geology can not fail to find much 

 in this small book (which he can easily slip 

 into his pocket) which will be of help to him. 

 This origin explains a certain dogmatic 

 character. There is no discussion of various 

 methods or of dubious points, but one good 

 method is given for solving various geological 

 problems. In no other way could so much be 

 packed into so small a space. The style is 

 clear and simple and there is no one better 

 qualified to prepare such a book than the 

 author — the Chief Geologist of the U. S. 

 Survey. 



Most of us will, I think, in reading such a 

 book, feel as we do in reading the Bible, that 

 we have left undone things which we ought to 

 have done and done things which we ought not 

 to have done. In helping one to make the 

 necessary observations, the second part, which 

 includes a set of schedules of the observations 

 which should be made in studying land forms, 

 petrology, geological structure, glacial de- 

 posits, ores and various classes of economic 

 materials, will be of great help and suggestive- 

 ness to any one who has occasion to make 

 inquiry in these lines. One might, perhaps, 

 ask whether the absence of any schedule with 

 regard to water investigations implies that the 

 hydrographers know nothing about geology or 

 that the geologists have little use for water! 

 The first part includes not only suggestions 

 for the field geologist along every line, but 

 helps to obey these suggestions, from unit 

 rations to mathematical formula;. It can be 

 most highly recommended not merely to geolo- 

 gists and scientific men, but, as many of the 



