56 TBLEGONY AND REVERSION. 



mental impressions on the offspring. The tradition influenced 

 the ancient Greeks ; it still holds sway in modern Eome. 



The Lamarchian TrunTc. — In 1801 and again in 1809 

 Lamarck ventured to suggest that the various species of 

 animals had not (as was then all but universally believed) 

 been separately and specially created. Like Erasmus 

 Darwin, he believed that from a few simple forms all the 

 varieties and species of animals had been gradually evolved. 

 He accounted for the progressive increase in organisation 

 in the vegetable and animal kingdoms by saying that as 

 new organs were needed they appeared — partly through 

 transcendental influences, — and that the modifications 

 acquired by one generation wei-e handed on to the next. 

 In other words, Lamarck believed that the evolution of 

 plants and animals had been mainly accomplished by the 

 transmission of acquired characters, by the inheritance, 

 generation after generation, of functionally produced modi- 

 fications, together with changes resulting from the influence 

 of the surroundings or environment. To give the familiar 

 examples, Lamarck believed that the necks of the ancestors 

 of the giraffe had been lengthened by generation after 

 generation stretching them to reach the higher foliage ; 

 that webbed feet had been acquired in, e. g., aquatic birds 

 and mammals, by the toes being outstretched when swim- 

 ming; and, to take another example, Lamarck believed that 

 certain four-footed reptiles, by wriggling amongst shrubs 

 and grasses, by elongating their bodies and losing their 

 worse than useless limbs, had been gradually transformed 

 into snakes, while others by acting in a different fashion 

 had developed into birds. However incredible it may to 

 some appear, Lamarck's theory in a modified shape still 

 forms part of the creed of not a few biologists in Europe 

 and of a still larger number in America. Some of the Neo- 

 Lamarckiaus may, like Lamarck, believe that improvements 

 partly result from the operation of some transcendental 

 principle working in predetermined lines — believe in a kind 

 of teleology.* 



* It will, I think, be allowed that most people who come into touch 



