664 



THE AMERICAN NATURALIST [Vol. XLVI1I 



Furthermore, the plasticity of plant structures made the 

 application of the doctrine of natural selection to sup- 

 posed adaptations untenable, and this type of explanation 

 has received little more attention with botanists than have 

 Lamarckian speculations with zoologists. The adaptation 

 characters of plants can not ordinarily be used as taxo- 

 nomic criteria (Coulter, '08). 



6. The Measure op Values in Biological Science 

 One hears reference to pure science as something quite 

 apart from applied science. It is indeed true that inves- 

 tigators in pure science are to some degree prompted to 

 push forward in research by interest in the problems for 

 their own sakes. But the human mind does not work long 

 isolated from practical affairs or the main channels of 

 human interest, and it is doubtful if the pure-science 

 investigator continues long in this way. Observations are 

 soon connected up in some way, actual or possible, with 

 some human interest, be it as remote as the improving of 

 human stock in remotely future generations. Thus "pure 

 science" denned as investigation for investigation's sake 

 hardly exists so far as the pure-science workers are 

 concerned, but may be best defined as an indirect method 

 of attacking problems of general importance. It differs 

 from applied science in that application to practical 

 problems is not its aim, though the estimated value of 

 theories and results in "pure" science are often greatly 

 modified by applicability to practical questions. 



Certain problems and groups of facts in biology are 

 sometimes referred to as fundamental. Some one has 

 said that a fundamental problem is one the solution of 

 which biologists have decided will give greatest progress. 

 It is doubtless true that a few leaders reach snch decisions 

 with regard to particular questions, but the real causes 

 of their general acceptance as fundamental are social 

 and imitative. Thus when one investigator or a small 

 group of investigators arrives at such a decision many 

 others usually become active along the same lines largely 

 because it is a popular topic. Thus under the influence 



