640 



NAtUHe. 



[February ii, 19 15 



that he has executed this hiborious piece of work 

 with care arid skill. 



As the author must have been saturated with 

 Lamarck's views for a prolonged period, it is in- 

 terestingf to read his introduction, where the essen- 

 tials of Lamarck's teaching- are explained. \\'e 

 shall refer to a few. It is pointed out, for in- 

 stance, that Lamarck's picture of a continuous 

 scale of being from Monad to Man (the taxonomic 

 punctuation being simply a matter of convenience) 

 was associated with his denial that species had 

 ever become extinct. Apparently peculiar fossils 

 have, he maintained, their living representatives, 

 though they may not have been discovered. 



Reacting from the doctrine of fixity of species, 

 Lamarck went to the other extreme of exaggerat- 

 ing their instability. Evolution he believed to have 

 come about by minute steps only. The factors 

 were two- — an innate tendency to complexify and 

 the hereditary accumulation of changes induced 

 by peculiarities in function (use and disuse). 

 These peculiarities may have arisen as responses 

 to changes of environment, but he expressly ex- 

 cludes the direct action of the environment as an 

 operative cause. 



In discussing the question of the transmission 

 of modifications, Mr. Elliot refers to an interesting 

 and illuminating suggestion by Prof. MacBride 

 that hormones may afford a clue to a possible 

 modus operandi of transmission. Unless we have 

 misunderstood, a similar suggestion was made by 

 Mr. J. T. Cunningham in 1908, and the idea is 

 also implied in a passage in the " Creative Evolu- 

 tion " by Prof. Bergson, with whose "illusions" 

 Mr. Elliot is familiar. We refer to the point 

 simply because these coincidences of thinking are 

 always of interest. 



Mr. Elliot says on p. 49 that if environmental 

 factors come into action after birth or before it 

 in the course of development they produce a modi- 

 fication, apparently not heritable. If they come 

 into action before development begins, they pro- 

 duce a variation which is heritable. In his ex- 

 ceedingly important experiments on Simocephalus, 

 Dr. W. E. Agar has shown that a change induced 

 in the egg-cells along with the body of the parent 

 had its influence on the individuals developing 

 from these ova, and slightly on the next genera- 

 tion, and then waned away. In the light of this 

 fact and Dr. Agar's interpretation, Mr. Elliot's 

 view requires correction. 



One of the interesting conclusions of Lamarck's 

 physiology was that nervous impulse is due to a 

 "nervous fluid," which is an "animalised" form 

 of the electric fluid. He reached this conclusion 

 by showing that no other theory worked, and Mr. 

 Elliot finds obvious satisfaction in showing that 

 NO. 2363, VOL. 94] 



this is the per exclusionem .method Used by Dr. 

 Hans Driesch and others to prove the existence of 

 a vital force or Entelechy. The fallacy is the 

 familiar one that we have first to be sure that 

 all the possible alternatives are before us. Mr. 

 Elliot simplifies things by assuring us that "every 

 event, that receives a scientific explanation, is 

 analysed into some particular combination of 

 matter and material energy." A reflex action, for 

 instance, is "of a purely mechanical nature." But 

 this, like the vitalist's declaration that there must 

 be a "vital force," is an assertion that outstrips 

 its evidence, as Prof. Sherrington 's' work plainly 

 shows. 



Lamarck was shrewdly opposed to postulating 

 entities such as a vital principle or even "esprit," 

 and was on the whole mechanistic. Yet we must 

 bear in mind that one of the distinctive features of 

 his teaching was the important evolutionary role 

 which he ascribed to the "emotions of the inner 

 feeling," which are excited by "needs," and 

 give rise to actions at once satisfying and trans- 

 forming. Of this and many other matters Mr. 

 Elliot has much that is interesting to say, though 

 we think his philosophy is sadly out of repair. 



J. A. T. 



genejral and specialised geology. 



(i) A First Book of Geology. By Dr. A. Wil- 

 more. Pp. vi + 141. (London: Macmillan and 

 Co., Ltd., 1914.) Price is. 6d. 

 (2) An Introduction to the Geology of New South 

 Wales. By C. A. Sussmilch. Pp. xviii + 269. 

 Second edition. (Sydney : Angus and Robert- 

 son ; London: Oxford University Press, 1914-) 

 Price 75. 6d. net. 

 (i) T^R- WILMORE'S "first book" of geo- 

 X_^ logy presumably completes the admir- 

 able series that includes, under the care of the 

 same publishers, the works of Prof. Watts and Sir 

 Archibald Geikie, and culminates in the latter's 

 monumental "Text-book." The landscape illus- 

 trations are clear and well chosen ; we may speci- 

 ally mention Mr. Harrison's tors on Dartmoor, 

 and the Sligo peat-bog, with Ben Bulben in the 

 background, by Mr. Welch (of Belfast, not 

 Dublin). Without any appearance of crowding, a 

 remarkable amount of fundamental information is 

 included here in 140 pages. Practical work is 

 encouraged, and the book is well suited for 

 schools. The fact that the dip is the greatest 

 possible angle of those that might be read with the 

 clinometer should be emphasised on p. 32. The 

 fine picture of Vesuvius on p. 43 represents the 

 well known eruption of 1872, not 1892. A figure 2 

 is missing from the olivine formula on p. 54; 

 water is omitted from that for gypsum on p. 94; 



