96 THE DATA OF BIOLOGY. 



1. All account of the structural phenomena presented bv 

 organisms. And this subdivides into : — 



a. The structural phenomena presented by individual 



b. The structural phenomena presented by successions 

 of organisms. 

 2. An account of the functional phenomena which or- 

 ganisms present. And this, too, admits of sub-division into : — 



a. The functional phenomena of individual organisms. 



b. The functional phenomena of successions of organisms. 

 8. An account of the actions of Structure on Function, 



and the re-actions of Function on Structure. And like the 

 others, this is divisible into : — 



a. The actions and re-actions as exhibited in individual 

 organisms. 



b. The actions and re-actions as exhibited in successions 

 of organisms. 



4. An account of the phenomena attending the production 

 of successions of organisms : in other words — the phenomena 

 of Genesis. 



There is, indeed, another mode of grouping the facts of 

 Biology, with which all are familiar. According as they 

 are facts of animal or vegetal life, they may be classed 

 under the heads of Zoology and Botany. But this di- 

 vision, though convenient and indeed necessary for practi- 

 cal purposes, is one that does not here concern us. Dealing 

 with organic structures and functions in connexion with 

 their causes, conditions, concomitants, and consequences, 

 Biology cannot divide itself into Animal- Biology and Yege- 

 tal-Biology ; since the same fundamental classes of phe- 

 nomena are common to both. Recognizing this familiar 

 distinction only as much as convenience obliges us to do, let 

 us now pass on to consider, more in detail, the classification 

 of biologic phenomena, above set down in its leading outlines. 



§ 38. The facts of structure which an individual or- 



