,^_ SOME NEW BOOKS. 787 



history beyond the collection of specimens ; and for this, his abun- 

 dant collection of facts and experiments dealing with variation and 

 the influence of changed environment will no doubt suffice. But, 

 alas ! if these readers set up aquaria, and in the name of scientific 

 investigation diligently tease their inhabitants; for experimental work, 

 to be of the slightest value, must be done in a much more critical 

 and disciplined way than they are likely to learn from Dr. de Varigny. 

 At least that is so if his observations of animals and plants at all 

 resemble his observations of the authors he cites. Take one or two 

 examples. 



On page 107, after an account of Yung's experiments on the deter- 

 mination of sex in Tadpoles, he proceeds : — " Thus food, and the nature 

 of food, has much to do in the determination of sex. The same is the 

 case with bees, where the production of queens, workers, and drones 

 is in great part a matter of nutrition. A worker larva may be reared 

 into a queen, if royal food is provided." Quite so; but if Dr. de 

 Varigny had read with any attention even the short account given by 

 Geddes and Thomson (to whose book he refers on the same page) he 

 would have seen that, while royal food may ripen the latent sex of a 

 worker, a different factor has to do with the distinction between male 

 and female. 



On pages 223 and 224 the author gives an account of the modi- 

 fications produced by cultivation on Bacillus anthracis, and then pro- 

 ceeds : " It seems, then, that Professor Weismann goes certainly too 

 far when he asserts that we have no proof of the direct production of 

 transmissible changes by means of external influences. It maybe said 

 that he restricts his denial to the metazoa." It may indeed ! In this 

 restriction and its consequences is the very gist of Dr. Weismann's 

 difficulty about the transmission of acquired characters. 



On page 225 the author writes : — " On the other hand, we 

 possess, in the facts of domestication and cultivation, a large number 

 of cases of variation— which occurs in every part — due to environ- 

 ment, and transmitted by inheritance in various degrees." If the 

 statement were true there would be no controversy. 



On pp. 229 and 230 he quotes with approval from Le Conte 

 (Monist, April, 1891) his curiously inept classification of the factors of 

 evolution. Of the five heads, the first two are most interesting : — 



" First. — Presence of a changing eiwiromnent affecting functions, 

 and functions affecting structure, and the changed structure and 

 function inherited and integrated through successive generations 

 indefinitely. 



" Secondly. — Use and D/sz/s^oforgansre-actingon growth force, and 

 producing change in form, structure, and relative size of parts, and 

 such change inherited and integrated through successive generations." 



To include together an admitted truth and a disputed interpreta- 

 tion, so that denial of both may be attributed to those who differ 

 from one about the latter, is an old device of pohtical controversy ; 

 but it is unsuited to scientific writers, whose purpose is to reach the 

 truth rather than to confound their adversaries. P. C. M. 



Elementary Biology. By H. S. Campbell, M.D. London: Swan Sonnenschein 

 and Co., 1892. Price 6s. 



This excellently illustrated httle book includes all the types selected 

 by the conjoint Board of the Royal College of Physicians and Sur- 

 geons for the examination in Elementary Biology. It also goes 

 over the ground prescribed in the syllabus for that examination. 



3D 2 



