410 



SCIENCK 



[N. S. Vol. IX. No. 220. 



toxicological facts reported in the eleventh 

 chapter, indeed, support this view. 



The further inference from the theory, that 

 very labile but not yet organized protein sub- 

 stances possibly occur in jjlants, has also been 

 verified. An exceeding labile reserve protein 

 of an aldehyde nature was proved by Bokorny 

 and myself to exist in many kinds of plants ; 

 its characteristics are described in the ninth and 

 tenth chapters. 



Labile substances contain kinetic chemical 

 energy ; they contain certain loosely bound 

 atoms, which under the influence of heat be- 

 come more mobile than in case of a more stable 

 arrangement. As a result chemical reactions 

 are caused, the energy of these atoms being 

 transferred to certain susceptible substances 

 (sugar, fatty acids), which are thus drawn into 

 a state of higher reactive power, especially with 

 the otherwise indifferent oxygen of the atmos- 

 phere. In other words, catalytic actions are 

 produced through a charge with chemical en- 

 ergy. The proteins of living substances ap- 

 pear as relatively firm structures in which sepa- 

 rate labile atoms perform great oscillations. 

 This conception is essentially different from 

 that of Pfliiger and Detmer, both of whom as- 

 cribe to all atoms in the plasma-proteins such 

 an intense state of motion that a dissociation 

 results, to be followed by a similarly energetic 

 regeneration. Pfliiger says : * " I do not ex- 

 pect to meet with any opposition if I consider 

 the living matter as not only being astonish- 

 ingly changeable, but steadily decomposing." 



Yet, when we consider that a minimal attack 

 of extremely small quantities of a poison will 

 produce the death of a cell, one may well 

 doubt whether such a metabolism as Pfliiger 

 assumes would not sooner lead to death than to 

 a possibility of regeneration. Neither can we, 

 therefore, agree with Verworn when he says : f 

 "The life process is the sum-total of all pro- 

 cesses connected with the building-up and de- 

 struction of the ' biogens, ' or, ' ' life consists in 

 the metabolism of the albuminous bodies." A 

 more correct definition would be the following : 

 Life is the sum-total of the effects made possible 

 by the labile nature of the plasma-proteins and 



* Pfliiger's Archiv 10, p. 311. 



t Allgemeine Physiologie, 2d edition, p. 509. 



their respiratory activity, and governed by the 

 specific tectonic of the enei'gides and of the ac- 

 tive paraplastic structures.* 



The nature of the living matter is in the first 

 place determined by lability and organization, 

 that is, by a systematic kind of motion in a 

 structure (tectonic) of labile proteins. The 

 principle of organization is not yet known. 

 Even if we assume with Pfiiiger that the pro- 

 cess of organization consists merely in a poly- 

 merization, the complicated details in genera- 

 tion and karyokinesis, would still defy explana- 

 tion, and the genetic differentiation would not 

 become better intelligible. Difficult problems 

 are here facing us. Still it may be considered a 

 slight advance to know at least a little more 

 about the cause of respiration and the chemical 

 energy of the cells than formerly. It is the 

 lability of the plasma-proteins, which, sup- 

 ported by the eflfects of light, leads to the build- 

 ing-up of the carbohydrates in the green plants 

 out of carbon dioxide and water with separa- 

 tion of oxygen. It is also this lability which 

 assists in combining the organic substances 

 with oxygen and renders the obtained energy 

 applicable to physiological work. 



In addition to the well-known fact that all 

 life functions are based upon the energies of the 

 sun, it must be inferred that the lability of the 

 plasma-proteins is necessary to transform this 

 sun energy into vital action. 



Albert F. Woods. 



Division of Vegetable Physiology and Pa- 

 thology, U. S. Depaetment of Ageicultuee. 



Physical Geography. By William Moeeis 

 Davis, assisted by William Henry Snyder. 

 Boston, Giun & Company. 1898. Pp. 431. 

 Professor Davis well states in his preface the 

 central principle of this volume: "Physio- 

 graphic facts should be traced back to their 

 causes and forward to their consequences." 

 We find thus the widest departure from the 

 piecemeal description and recital of facts, of 

 most works in physical geography. We should 

 expect this from one who has long been eminent 

 as a student and teacher of the science and who 



* Kupffer designates the contractile substance of 

 the muscular fibrille, the nervous fibre and the red 

 blood corpuscles as ' paraplastic ' formations. 



