622 



SCIENCE 



[N. S. Vol. XXXIII. No. 851 



two most important maladies of that crop. 

 That the viewpoint of the author is that of 

 parasitology rather than pathology is further 

 shown by the omission of any discussion of 

 the physiology of disease. The very brief ap- 

 pendix chapter on physiology has no relation 

 to the rest of the book. 



From the standpoint of the lay reader it is 

 feared that the space devoted to remedial 

 measures is in most cases not sufficient, nor 

 the recommendations as definite and specific 

 as the needs of practise require. 



The large number of minor diseases men- 

 tioned without adequate description will also 

 confuse the inexperienced student. 



Some more serious errors occur. The re- 

 viewer knows of no warrant for the statement 

 on page 445 that Microsphwra alni practically 

 destroys the pecan crop in the south in certain 

 years. This fungus is one of the least harm- 

 ful of the pecan parasites. Stigmonose of 

 carnation is not mentioned while there is a 

 reference to a more obscure bacterial disease. 

 The discussion of mosaic disease of tobacco 

 and tomato would be cleared by including 

 Woods's results.' 



Absurdly large losses are attributed to cot- 

 ton anthracnose in Georgia, and the injury to 

 tomatoes from Phytophthora is overstated. 

 The description of Bordeaux injury is incor- 

 rect, as is also the statement that blossoms are 

 killed and the lives of bees endangered by 

 spraying with Bordeaux. 



All workers in plant pathology should pos- 

 sess this book and it will be useful to farmers, 

 fruit growers and all who are interested in 

 growing plants. There has long been urgent 

 need for a treatise on American plant diseases 

 adapted to general readers, in which the 

 widely scattered and often unobtainable recent 

 publications should be summarized. This 

 book is intended to meet this need. 



W. A. Orton 



' Preliminary Report on the Peat Deposits of 

 Florida. By Roland M. Harper. Third 

 Ann. Kept. Pla. Geol. Surv., 1910, pp. 197- 

 375, pi. 16-28, tf. 17-30. 

 'Bulletin 18, Bureau of Plant Industry, 1902. 



The state of Florida because of its flatness, 

 its abundant ponds, lakes and swamps, its 

 ample, well-distributed rainfall and the ab- 

 sence of sediment-laden streams, affords ex- 

 ceptionally favorable conditions for the for- 

 mation of peat, and the present report is a 

 monumental disproof of that ancient and per- 

 sistent fallacy that peat is formed only in 

 high latitudes. 



For purposes of discussion the state is di- 

 vided by the author into fourteen more or less 

 natural divisions based chiefly upon topog- 

 raphy and vegetation, and these are shown on 

 a sketch map. The varied swamps of the 

 state are elaborately classified, more than 

 thirty types being enumerated and described 

 in more or less detail. The more common 

 plants of each are listed in the order of their 

 abundance. 



A few pages are devoted to fossil peat. Nu- 

 merous analyses of peat samples are given and 

 there is a chapter upon the utilization of peat. 

 This is followed by a reliable systematic cata- 

 logue of Florida peat-forming plants and the 

 report is concluded by a bibliography and a 

 good index. 



The report, as a whole, is well done and ex- 

 cellently illustrated by 13 plates and 14 text- 

 figures. While it is confessedly superficial, it 

 should be remembered that the economic de- 

 velopment of Florida at the present time would 

 hardly warrant the investment of the large 

 sum of money necessary for an exhaustive 

 study of its peat deposits. From the com- 

 mercial view point the present report is surely 

 ample enough to point the way to a utiliza- 

 tion of the more important peat deposits and 

 those which are favorably situated for ex- 

 ploitation. 



Dr. Harper approaches the subject from the 

 view point of the plant geographer, and it is 

 this aspect of the report which has the most 

 scientific merit and which will occasion the 

 widest interest. A more intensive study and 

 a much fuller treatment of the flora would 

 have been desirable from the standpoint of the 

 botanist, but for the reasons mentioned above 

 such a study was not practicable. 



