922 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Chemical Changes in their Relation to Micro-Organisms.* — 

 Prof. E. Frankland distinguishes between two kinds of chemical action 



(1 ) that in which substances brought into contact mutually undergo 



chemical change, and (2) that in which chemical change is effected in 

 one substance by contact with another, which itself apparently 

 suffers no alteration. 



The following definitions are proposed to distinguish animal 

 and vegetable organisms : — (1) A plant is an organism performing 

 synthetical functions, or one in which these functions greatly pre- 

 dominate ; it transforms actual into potential energy. (2) An animal 

 is an organism performing analytical functions, or one in which these 

 functions greatly predominate j it transforms potential into actual 

 energy. All micro-organisms appear to belong to the second class. 

 Oxidation is the essential condition of life. There are, however, 

 many other chemical transformations in v;-hich potential becomes 

 actual energy, and which therefore can support life. The author 

 describes the chemical changes produced by a large number of micro- 

 organisms, and points out that there is no break in the continuity of 

 chemical functions between micro-organisms and the higher forms of 

 animal life. It is true there are apparently certain sharp distinctions 

 between them. The enormous fecundity of micro-organisms and their 

 tremendous appetites seem to separate them from the higher orders of 

 animals. But this distinction is only comparative. It must be borne 

 in mind that an animal like a sheep converts much of its food into 

 carbonic acid, hippuric acid, and water, thus utilizing nearly the 

 whole of the potential energy, while the micro-organism as a rule 

 utilizes only a small portion. Those micro-organisms which have 

 been chemically studied produce, like the higher animals, perfectly 

 definite chemical changes. " The position of these organisms in 

 nature is only just beginning to be appreciated. It may safely be 

 predicted that there is no danger of their being spoiled by the petting 

 of sentimentalists, yet these lowly organisms will receive much more 

 attention in the future than they have done in the past." 



B. CRYPTOGAMIA. 



Cryptogamia Vascularia. 



Comparative Morphology of the Leaf in Vasciilar Cryptogams 

 and Gymnosperms-t — F. 0. Bower points out that if the doctrine of 

 Saehs and others that the living stem and leaf are to be regarded only 

 as expressions denoting certain relationships of the parts of the shoot, 

 be correct, the same mode of morphological treatment ought to be 

 applied to both. In treating of the leaf, authors have not attached 

 most importance to the mode of origin and sequence of appearance of 

 its several parts ; parts have been distinguished that are not morpho- 

 logically co-ordinate. The author finds that there is no justification 



* Nature, xxx. (1884) pp. 549-50. (Eeport of discussion at the Montreal 

 Meeting of the British. Association.) 



t Proc. Roy. Soc, ssxvii. (1884) pp. 61-5. 



