January 3, 1902 ] 



SCIENCE. 



23 



a general statement. It proves that the as- 

 sociative process in vertebrates is dependent 

 upon the cerebral hemisphere. "The assump- 

 tion of 'centers of association,'" says the 

 author, "is just as erroneous as the assump- 

 tion of a center of coordination in the heart. 

 Association is, like coordination, a dyuamical 

 effect determined by the conductivity of the 

 protoplasm. Associative processes occur every- 

 where in the hemispheres (and possibly in 

 other parts of the brain), just as coordination 

 occurs wherever the connection between two 

 protoplasmic pieces is sufficient. It is just as 

 anthropomorphic to invent special centers of 

 association as to invent special centers of 

 coordination." 



Finally, attention should be called to the 

 stress which in this valuable contribution to 

 the literature of comparative physiology is 

 laid upon the chemical and physical study of 

 protoplasm and its transformations. Ulti- 

 mately it would appear all physiological in- 

 vestigations resolve themselves into problems 

 of the physics of colloidal substances. 



In this imperfect and inadequate review of 

 Professor Loeb's book an attempt has been 

 made to indicate a few of the general tenden- 

 cies and conclusions which seem of prime im- 

 portance. There are a large number of inter- 

 esting experimental studies discussed in the 

 book which have not even been mentioned 

 here. We have taken the liberty to quote 

 freely from the text, and it is hoped that the 

 sentences thus selected to indicate the author's 

 point of view will in no case misrepresent him 

 because of their isolation. 



Egbert Mearns Yerkes. 



Cambeidge, Mass. 



Plant Life of Alabama. An account of the 

 distribution, modes of association and 

 adaptations of the flora of Alabama, to- 

 gether with a systematic catalogue of the 

 plants growing in the State. By Charles 

 MoHR, Ph.D. Contributions from the U. S. 

 National Herbarium. VI. Washington. 

 1901. 8vo. Pp. 921. 12 plates and 1 map. 

 The 'Plant Life of Alabama' is a note- 

 worthy addition to the list of works which 

 treat of State floras. The book consists of two 

 parts; one, of 127 pages, dealing chiefly with 



the floristics of the vegetation, the other, of 

 708 pages, containing a complete catalogue of 

 the flora. The first part will be particularly 

 welcomed by phytogeographers as the first 

 serious analysis of a portion of the vegetative 

 covering of the southeastern United States. 

 The value of this portion lies chiefly in the 

 observations and lists which it contains, as 

 no systematic investigation of the vegetation 

 has yet been made. The absence of recent 

 methods and the lack of detailed formational 

 analysis detract much from this part, though 

 the lapse of time between the completion of 

 the manuscript and its publication would 

 seem to indicate that this is not the fault of 

 the author. It is much to be regretted that 

 the author's death occurred before his book 

 finally appeared. 



The author sketches the history of the bo- 

 tanical exploration of Alabama, giving a brief 

 account of the labors of Bartram, Peters, 

 Buckley and others. This is followed by a 

 summary of the general physiographical and 

 climatic features of the State. Physiographic- 

 ally, the area considered falls into five re- 

 gions, the coastal plain, the region of crys- 

 talline rocks, the region of the coal measures, 

 the Coosa Valley and the Tennessee Valley. 

 The author gives a brief discussion of the gen- 

 eral principles underlying plant distribution, 

 in which he has imfortunately made use of 

 Merriam's divisions of the North American 

 continent, which are phytogeographically in- 

 correct. The formational treatment is based 

 upon the work of Willliomm and Warming. 

 The accurate classification of formations, how- 

 ever, as hydrophytic, mesophytic or xerophytic, 

 is hardly to be determined otherwise than by 

 actual physiometric investigation of forma- 

 tions, which have been tentatively determined 

 by means of floristic. The formational anal- 

 ysis of the vegetation is neither close nor 

 thorough, consisting for the most part of flor- 

 istic lists of the various habitats, with very 

 slight consideration of the interrelations of 

 the species which constitute the formation. 

 In some instances (page 65) the difficulty 

 seems to rise from the fact that the acquaint- 

 ance with the particular vegetation is at sec- 

 ond hand. 



