No. 496] ASPECTS OF THE SPECIES QUESTION 275 



that we have developed greatly elsewhere, but in this 

 particular we have remained medieval or worse than 

 that. I think we have abundant evidence right here that 

 there has been progress. This meeting this afternoon 

 would have been no more possible a dozen years ago 

 than it is now to separate out the species of Crataegus by 

 somebody who has not studied them during that time. 

 There has been something working. People have been 

 finding that there is something besides names and dates ; 

 something has occurred since 1753. It looks to me as 

 though it were hopeful. If there is anarchy, more of 

 that than anything else, it is a pretty good beginning to 

 start something that is not anarchy. 



However, I feel sure L shall not give up everything in 

 regard to our common notion of species and species' 

 names. I do hope that I shall know the white oak under 

 its proper name hereafter when I see it, and a few other 

 things like that ; and I think it is really important that 

 when we speak about certain things, of certain effects 

 and relations, we do understand what we are talking 

 about and that others may also understand. I think 

 it does make a difference as to whether we continue the 

 use-to take Dr. Arthur's first illustration-the definite 

 use of such terms as Bacillus anthraeis and Bacillus 

 typhosus, and the rest of them. If a writer is going to 

 discuss a subject in which these organisms play a part 

 and one that is vital to our existence and welfare, it is 

 surely desirable that we should have a correct interpre- 

 tation of what he means when he uses these terms. I 

 believe we are pretty near that meaning in regard to the 

 common organisms in the group of bacteria, so that we 

 know pretty well what is meant when such names as 

 those above are mentioned, though nobody will deny that 

 included among the organisms to which the names ap- 

 ply there are considerable differences. They are dif- 

 ferent in their sizes, if you come down to microbe meas- 

 urements; they differ certainly in their growth upon 

 different media, and I do not see why the physiological 



