792 



SCIENCE 



[N. S. Vol. XXXVI. No. 936 



protein metabolism investigations, have such 

 enlightening studies been published during 

 any like period as during 1911 and the first 

 half of 1912. The admirable work of Osborne 

 and Mendel on the physiological role of the 

 individual proteins, and of Folin and Denis 

 on the fate of the products of protein diges- 

 tion after absorption, came too late for in- 

 clusion in this edition. 



The author has succeeded admirably in ad- 

 hering closely to the physiological aspects of 

 protein metabolism, a difficult task, when a 

 vast amount of experimental data relating to 

 the chemical aspects of the same subject is 

 now available. This attitude is a desirable 

 one at the present time, when there is a strong 

 tendency on the part of text-book writers and 

 dietitians to assume that an adequate supply 

 of " building stones " in the diet is all that is 

 essential to insure physiological well-being 

 in the animal. The author has done a good 

 service to his fellow workers in producing a 

 treatise which will assist in creating new atti- 

 tudes toward the problems concerned, and to 

 the great number of teachers who follow the 

 original literature to but a slight degree or 

 not at all, in presenting in so clear a form, 

 the experimental lines of inquiry directed 

 toward the solution of problems of protein 

 nutrition, and the different points of view to 

 which these have led. 



E. V. McCoLLUM 



XJniveksitt of Wisconsin 



Scientific Results of the Voyage of 8. T. 



" Scotia" during the Years 1902-190Jt. Vol. 



III., Botany. Edinburgh, The Scottish 



Oceanographical Laboratory. 1912. 4to. 



Pp. X + 153, 12 pi., 1 chart. 



Nearly simultaneously with the publication 

 of this volume, now dedicated to his memory. 

 Sir Joseph Hooker, the dean of botanists and 

 the author of the " Flora Antarctica," passed 

 from his earthly labors. The botanical re- 

 sults of the Scottish National Antarctic Ex- 

 pedition are derived principally from two 

 summer visits to the South Orkneys and a 

 winter spent at Laurie Island in Scotia Bay; 

 a hasty visit to Gough Island; extensive col- 



lections of the algse of Weddell Sea; notes on 

 the botany of Ascension Island ; and incidental 

 collections made on the outward and home- 

 ward voyages. The report on the phytoplank- 

 ton will be issued later. 



The present volume opens with an introduc- 

 tion by Dr. Eudmose Brown on the problems 

 of Antarctic plant life. Recent explorations 

 have shown that the South Polar flora is in 

 some respects richer than has been supposed, 

 though its chief interest is derived from its 

 relations to the problems of geographical dis- 

 tribution and the origin of the Antarctic flora. 



With the exception of a doubtful fossil of 

 conifera, possibly of Devonian age, found 

 in Victoria Land, the knovm Antarctic fossil 

 plants are those obtained by Otto Nordens- 

 kjold from Hope Bay, Graham Land, ferns, 

 cycads and conifers indicating a warm moist 

 climate and abundant vegetation in Jurassic 

 times. The fossil Araucaria, Fagus, etc., 

 found at Seymour Island by the same expedi- 

 tion indicate the extension of somewhat sim- 

 ilar conditions into the Tertiary. 



The most striking feature of the Antarctic 

 flora is its poverty compared with that of the 

 Arctic. Spitsbergen in summer in Y9° north 

 latitude supports a hundred species of flower- 

 ing plants, while at the South Orkneys in only 

 61° south there is not a single species. In 

 Grant Land, in 81° and 82° north latitude, 

 Peary collected 57 mosses and 7 hepatics, more 

 than are known from the whole Antarctic 

 region south of latitude 60°. 



The explanation lies chiefly in the fact that 

 while the Arctic summer mean temperature is 

 well above the freezing point, that of the 

 Antarctic is practically always below it. An- 

 other factor is adverse to the establishment of 

 plants on the few snowless patches of Ant- 

 arctic land, namely, the presence of myriads 

 of penguins, which cover these areas with 

 their guano and trample them into mud when- 

 ever the temperature is above the freezing 

 point. The few sheltered spaces where mosses 

 occur are poorly suited to flowering plants. 

 Tet that their introduction is possible by nat- 

 ural causes is indicated by the discovery of 



