NATURAL SCIENCE. Feb.. 



are still pursuing experimental investigations, and if the same con- 

 clusions can be arrived at by a multiplicity of methods, biologists and 

 geologists will be constrained to acquiesce. 



The Influence on Development of Chemical Changes in the 

 Surrounding Fluid. 

 Curt Herbst, of Zurich, in the Zeitschrift fiir Wissenschaftliche 

 Zoologic (vol. Iv., p. 456), has pubhshed the results of an interesting 

 series of experiments on the eggs and larvae of Echmoids. He con- 

 cludes that sudden changes in the chemical composition of the sea- 

 water produce great changes in the larvae. But these changes are 

 due not to the chemical nature of the introduced material, but to 

 changed physical conditions-chiefly to changes of the osmotic 

 action between the water and the larv^. He hopes that such experi- 

 ments tend towards an understanding of normal development, and 

 indicate paths towards the remote goal of a casual interpretation of 

 Hfe-history. By changing the chemical conditions, he hoped to hnd 

 whether the form of a larva at all depended on the composition of 

 the medium in which it grew. His first result is against a 

 chemical, in favour of a physical influence. The form of the larva 

 varies with osmosis within and without the larv^a. Clearly Curt 

 Herbst— like so many other zoologists— has not abandoned hope of 

 resolving vital actions into their chemical and physical elements. 



Vitalism. 



At the present time, indeed, there is abundant evidence of a funda- 

 mental change in the attitude of biologists. Among zoologists, one 

 often hears it said that morphology is played out. By this it is 

 apparently meant that the obvious problems of microscopic anatomy 

 are done with ; that series of sections have been made of all the more 

 famiUar animals and organs, and that three weeks at the seaside with 

 borax-carmine and a rocker microtome, no longer result in an epoch- 

 making paper, containing a hypothetical ancestor, and a brand new 

 pedigree. This is, no doubt, very depressing, but there are still 

 problems in abundance to solve, and we are far from regarding the 

 microtome as obsolete. On the other hand, it is undoubtedly the 

 case that the pristine enthusiasm for microscopic anatomy resulted 

 in a neglect of many other sides of zoology. Examine the scientific 

 journals of from four to twenty years ago, and you shall find hardly 

 a word of that side of biology Professor Lankester has called 

 Bionomics. At the present time, in almost every journal one sees 

 studies on variation, experimental work on development, investigations 

 of Uving things as aUve. 



It is, however, among physiologists that the revival of this side 

 of biology is most apparent, and it is among physiologists that the 



