TRANSMISSION OF ACQUIRED CHARACTERS. 415 



results of the new conditions, and there is no evidence for the 

 occurrence of acquired characters, using the term in its restricted 

 sense. 



I now come to the last botanical fact brought forward by 

 Hoffmann in support of the transmission of acquired characters. 

 He states that specimens of Solidago mrgaurea brought from the 

 Alps of the Valais, commenced flowering in the botanical garden 

 at Giessen, at a time which differed by several weeks from that 

 at which specimens from the surrounding country, planted beside 

 them, began to flower. In other words, the time of flowering 

 must have been fixed by heredity in the alpine Solidago, for the 

 external conditions would have favoured a time which was simul- 

 taneous with that of the Giessen plants. 



What conclusions can be drawn from these facts ? Hoffmann of 

 course sees in them the proof of the transmission of acquired 

 characters, but this presupposes that the time of flowering was 

 originally an acquired character. Hoffmann indeed appears to 

 entertain this opinion when he somewhat vaguely states that the 

 time at which flowering begins has been acquired by accommodation 

 that is by the influence of climate during a long series of 

 generations, and has become hereditary. But what does Hoffmann 

 mean by ' accommodation ' ? He presumably means that which, 

 since the appearance of Darwin's writings, has been generally 

 called adaptation : that is a purposeful arrangement, suited to 

 certain conditions. The majority of biologists have followed 

 Darwin in believing that such adaptations have been produced by 

 processes of natural selection. Hoffmann seems to imagine that 

 they have arisen in some other way : perhaps he believes, with 

 Nageli, that they have been directly produced by external in- 

 fluences. 



The fixation of the time at which flowering begins, is an 

 adaptation which formerly could have been very well explained 

 as the direct result of external conditions. The question we have 

 to decide is whether such an explanation is the true one. We 

 might imagine that the plant would be forced into quicker develop- 

 ment by an earlier appearance of the warm season. Hence when 

 transferred into a warmer climate the plant would at first flower 

 rather earlier, the habit would then be transmitted, and would 

 increase in successive generations from the continued influence 



