PROCEEDINGS OF THE OHIO ACADEMY OF SCIENCE. 311 



Gnomic titles per annum has increased three or four fold within 

 the last two decades, while the quality of work done has im- 

 proved greatly. At present, no other kind of botanical activity 

 produces one-fourth as many titles as does taxonomy, while all 

 other phases combined scarcely j^roduce twice as many as this 

 one alone. However, we may not judge wholly by increase in 

 output and improvement in quality ; for it is well known that 

 the difficulties of taxonomy, at times, threaten to wreck the 

 science. 



The species problem is perhaps the greatest difficulty. The 

 main criteria of species are divergence and isolation, but these 

 can be ascertained only by laborious biometric methods. Recent 

 suggestions regarding centers of variation, about which degrees 

 of divergence or isolation may be measured and plotted, look 

 plausible ; but most new species are still described without such 

 laborious ])rocesses. 



Recent studies in physiology, ecology, mutation, Mendelism, 

 experimental morphology, and experimental evolution have 

 proved that there exist in nature distinct forms, perhaps rarely 

 those of our manuals. We know also that many of our de- 

 scriptions represent compound species. Either we must attempt 

 to treat real species, with great increase in numbers and with 

 attendant difficulty, or we must allow species to stand for com- 

 pound-conceptions and let those who wish to analyze further 

 use third-place names, numbers, or some other manner of desig- 

 nation. Stich a method would furnish a stopping place for those 

 who do not care to follow the taxonomist beyond the compound 

 conception. The segregates should then approach true species 

 as nearly as may be. In spite of many suggestions regarding the 

 species problem, taxonomy is holding its course ; not because 

 taxonomists do not recognize the need of reform, but because 

 they are not certain that any of the schemes proposed are feasi- 

 ble, or that the theories on which they are based, in part, will^ 

 stand the test of further research. 



Physiological species have been recognized recently among 

 bacteria and certain fungi, and there is some basis for such 

 species where morphological characters are obscure or lacking. 



