June 10, 1904.] 



SCIENCE. 



883 



as holdfasts; Kraemer on the epidermis, 

 hypodermis and endodermis of angiosperm 

 roots; Grimme on the flowering period of 

 German mosses— a detailed and instructive 

 paper; W. E. Britton on the anatomical 

 features of the plants of the Connecticut 

 sand plains; Bray's anatomical studies of 

 desert plants; Parkin and Pearson on the 

 anatomical characters of the plants of the 

 Ceylon Patanas. These latter authors are 

 surprised to find that the structures are as 

 xerophytic in the wet as in the dry prairies, 

 although it is nearly fifteen years since 

 Schimper showed that xerophytes may be 

 typical of certain wet habitats. 



In ecological phytogeography the closing 

 year has witnessed a considerable display 

 of literature in America and England. 

 Possibly no preceding year has afforded so 

 many contributions. In our own country, 

 one must give a prominent place to Gan- 

 ong's paper on the Bay of Fundy marshes, 

 a paper giving the results of the author's 

 studies during several years in one of the 

 most interesting physiographic areas in the 

 world. As many of us know. Professor 

 Ganong has postponed from year to year 

 the publication of this paper, fearing lest 

 errors might creep in that the study of just 

 another season would rectify. Would that 

 many another might heed his caution, and 

 spare the world the undigested results of a 

 week's ecological excursion! The com- 

 pleteness of detail and the accuracy of 

 statement in Ganong 's paper may well 

 serve as models to working ecologists. 

 Probably the harshest criticisms which his 

 paper will receive are contained in his own 

 concluding remarks. One of his sugges- 

 tions, in addition to those already noted, 

 may be mentioned here, viz., the necessity 

 of finding a means of estimating quantita- 

 tively the biological factor, i. e., the exact 

 influence of competition and cooperation in 

 determining the vegetation of a plant asso- 

 ciation. Another worker, and the only one 



who has so well exploited liis particular 

 field in America, is Bruce Fink, so long and 

 so favorably known for his lichen studies; 

 his recent development of lichen associa- 

 tions has added materially to our knowl- 

 edge. The speaker has long felt that 

 lichens ai^e among the most interesting of 

 plants ecologically, because they are so 

 closely related to the unmodified physical 

 environment. If any plants will show 

 whether purely chemical factors are of in- 

 fluence in distribution, we should expect 

 rock lichens to be of service in this regard. 

 Apropos of this question of physics versus 

 chemistry, one must mention the recent 

 bulletin of Whitney and Cameron, in which 

 the physical factor is given the dominant 

 place. This view has been accepted readily 

 by most ecologists, ever since Warming, 

 following Thurmann and others, so clearly 

 outlined the overwhelming importance as 

 an ecological factor of the physics of the 

 soil in relation to water. Other important 

 American papers are: Livingston on the 

 vegetation of Kent County, Michigan, pre- 

 senting a model detailed map which repre- 

 sents a type of illustration too infrequent 

 in American ecology ; Transeau on the dis- 

 tribution of the bog societies of North 

 America ; Harshberger on the vegetation of 

 mountainous North Carolina. In Britain 

 the work of the lamented Eobert Smith has 

 been continued by his brother, who in co- 

 operation with others has given two papers 

 dealing with the vegetation of Yorkshire. 

 Several papers of more than ordinary in- 

 terest from the view point of physiogTaphic 

 ecology, apart from Ganong 's paper on the 

 Bay of Fundy marshes, are as follows: 

 Cajander's study of the alluvial vegetation 

 of the Lena Eiver, containing excellent 

 analyses of phytogeogTaphic terms as well 

 as discussions on the genetic succession of 

 associations; Penzig's study of the develop- 

 ment of vegetation on Krakatoa since 

 Treub's visit some years since; Hayren's 



