ioo6 LIFE : OUTLINES OF GENERAL BIOLOGY 



repressive tradition of every old human institution or society; yet 

 (as with that) there may also come a time in the history of a strongly 

 stabilised form of life when at some point it cannot but burst its 

 hereditary bonds ; and so may even set out on a more or less contrary 

 line of development : witness that oscillation from floral exaggeration 

 to vegetable predominance alread}^ illustrated, as by Asparagus, etc., 

 and even conversely, as with fiower-rich weeds, and we mention 

 Masdevallia especially. Much as a young human individual has often 

 to choose between failure and re-adaptation in a changed or new 

 environment, so we see in the importation of new plants, or (say) 

 insects, into a country new to them: for there they either tend to 

 die out, or to grow and propagate more vigorously; indeed, often to 

 veritable pests, thus calling for the use of checks, like the importation 

 of their home enemies, now so frequently called for by agriculturists 

 and foresters. Sometimes the imports show vegetative changes as 

 well, like the immense thickness of watercress stems in New Zealand 

 rivers. Variations from such geographic change may not be fixed 

 within the short period of experiment, like Bonnier's Paris seedlings 

 altered by Alpine environment, yet not retaining this on their 

 return. Yet after all we could hardly expect any other result : but 

 a case like that of ordinary European deciduous peaches and plums 

 becoming evergreen in the climate of Reunion and yet so far 

 keeping true on return to their usual conditions, goes far to show that 

 environmental conditions may bring about more or less transmissible 

 variation, as also do Tower's experiments on the Colorado beetle. 

 Nor can the lines of research undertaken by the unfortunate 

 Kammerer be entirely abandoned. 



Returning to Heredity, what does it mean, if not fundamentally 

 continuance of the growth impulse, and its guidance, on abbreviated 

 — that is to say accelerated — lines: so why should this develop- 

 mental impulse stop? The inheritance of Proteus is like that from 

 Prometheus — not of mere yolk like coals, not mere building-plasm 

 even, but of life, like fire. This is not postulating any mystic 

 power in growth: it is the mechanist who is postulating a sudden 

 hereditary limit to its creativeness ; but such arrest is more 

 simply explained by the attainment of maturity enough for 

 reproduction. 



In this connection it is interesting to note, as in going through a 

 garden or herbarium, how many species and varieties are essentially 

 definable in terms of the different characters presented by their 

 vegetative system, yet with practically little or no change of flower; 

 as for conspicuous instances among the composites, of which the 

 floral distinctions are so much smaller and subtler than most, 

 whereas, in so many other groups, it is the flowers which present the 

 conspicuous characters, with but little or no apparent variation in 

 foliage and habit. To discriminate the characters of what we may 



