432 



SCIEl^CE 



[N. S. Vol. XLII. No. 1082 



An Outline of Modern Work hearing on the 



Theory of Descent: J. J. Wolfe. 



Previous to 1900 the evolutionary hypothesis 

 stood practically aa Darwin left it in 1859. Dur- 

 ing the intervening years a tremendous mass of 

 facts accumulated which tend to support it, but on 

 the other hand some weighty objections have also 

 been ofEered. These were, however, apparently met 

 by the mutation theory which appeared in 1901, 

 but unfortunately it has latterly encountered even 

 gi-aver difiSculties than Darwinism itself. Its 

 critics, Jeffrey in particular, have brought forward 

 very strong evidence tending to identify the phe- 

 nomena of mutation with hybridization. If this 

 criticism shall stand, mutation, is robbed of any 

 just claim to being an explanation of evolution. 



On the other hand, the work of Johanssen and 

 others appears to demonstrate that individual 

 variations are not heritable and all that selection 

 can achieve is to resolve a species into its com- 

 ponent elements, the so-called "pure lines," and 

 choose that pure line manifesting the character in 

 question developed to its highest degree. It can 

 not carry the development of this character one 

 whit beyond the limit attained by the species as a 

 whole. 



Now, if mutation is but the reappearance of 

 some recessive character, segregating out from a 

 long and complex process of hybridization in ac- 

 cordance with Mendelian principles, as De Vries's 

 critics seem to have rendered highly probable; and 

 if variation in the Darwinian sense be non-herit- 

 able, as the pure line investigations appear to 

 show, how has the transition from one species to 

 another occurred? That this has repeatedly taken 

 place would seem to be beyond intelligent doubt. 

 !Por answer, so far as the author can see, we are 

 limited to two views. "We must either assume the 

 inheritance of acquired characters, or that all char- 

 acters were present in the primordial germ cell. 



As regards the inheritance of acquired charac- 

 ters, much work has accumulated both for and 

 against its acceptance. On the zoological side in 

 particular experimentation tends to support the 

 view that acquired characters are non-heritable, 

 while on the botanical side the tendency is per- 

 haps in the other direction. The germ tissues in 

 plants are not as early set apart from the soma as 

 in animals, and are not nourished in an environ- 

 ment so constant and so well protected from en- 

 vironmental effects. Perhaps these facts have 

 some bearing on the question. Nevertheless, any 

 such broad generalization found true for plants 



would also be true for animals, even if its opera- 

 tion could not be so easily and clearly observed. 



The alternative hypothesis proposed by Bate- 

 son, that all characters were present in the primal 

 organisms, while not a very satisfying view, finds 

 a parallel in the development of the adult from 

 the egg. The biological world is pretty well agreed 

 that every important character manifest in the 

 adult is represented in some way in the germ 

 cell. If then the mature individual has arisen by 

 differentiation and specialization from a single 

 cell, manifestly it is not unthinkable to suppose 

 that higher animals were likewise represented in 

 the primordial protozoa. 



With the evidence before us, conflicting as it 

 is, it is clearly impossible at the present time to 

 say how evolution has occurred, yet, if personal 

 opinions are not out of place on an occasion of 

 this kind, it may be said that the inheritance of en- 

 vironmental effects seems destined to play a more 

 important part in the final solution of organic 

 descent than is accorded it at the present time. 



Besmotropy: Alvin S. Wheeler. 



The first case of keto-enol isomerism among the 

 phenols of the naphthalene series was recently re- 

 ported by Willstaetter and Wheeler. Juglone, a 

 dyestuff in green walnut shells, yields on reduc- 

 tion 1, 4, 8-trihydroxynaphthalene, melting at 

 152°. After once being melted it melts there- 

 after at 96°. Since this type of compounds is 

 very sensitive to alkalies, weakly basic reagents as 

 semicarbazine and phenylsemiearbazine were em- 

 ployed to detect the carbonyl group. The lower 

 melting product was found to be the ketonic form. 

 Some work, not yet published, on 1, 4, 5, 6-tetra- 

 hydroxynaphthalene reveals another case of this 

 nature. Here, however, it has been impossible to 

 separate the two forms, the compound melting at 

 154° responding readily to both enolic and ketonic 

 reactions. Numerous isomerization methods fail 

 to reveal another form. The application of 

 Knorr's ferric chloride and Kurt Meyer's bromine 

 method to approximate the relative amounts of the 

 isomers present is not practicable to the above 

 cases. Ferric chloride oxidizes the compounds to 

 quinones while bromine enters the ring of either 

 form. 



The S-H Waterwheel and Pump for Farm Water- 

 works: T. F. HiCKERSON. 



The Hutehison-Hickerson waterwheel and pump, 

 recently invented by E. B. Hutchinson of Wilkins- 

 burg. Pa., and T. F. Hickerson, of Chapel Hill, 

 N. C, is a discovery of a new application of the 



