Fink: Nature and Classification of Lichens 237 



pressed in figures without exponents, may be omitted in consider- 

 ation of the tables by those who do not care to go into this rather 

 difficult detail. 



The total number addressed in each group of botanists indicates 

 the policy employed in selecting botanists to whom to write. The 

 opinions of lichenists were especially sought, even to the extent 

 of addressing two or three amateurs in this field. So the number 

 of lichenists addressed is somewhat above the average number 

 in the other groups, though lichenists are few in number. After 

 lichenists, mycologists were especially sought ; and a large number 

 of pathologists was secured because mycologists are so often also 

 pathologists. In any consideration of classification, the views of 

 a considerable proportion of the great number of morphologists 

 and anatomists must be taken into account. Physiologists were 

 addressed with a view to ascertaining what they might say about 

 the relation of the peculiar biological condition in lichens to clas- 

 sification. Finally, a sufficient number of systematists, other than 

 lichenists and mycologists, was consulted to ascertain how wide 

 a view these persons might have regarding problems of classifi- 

 cation in general and the classification of lichens in particular. 

 Those who expressed no opinions or none that could be inter- 

 preted and recorded are two amateur lichenists, one mycologist, 

 one morphologist, one anatomist, one physiologist and three sys- 

 tematists. Corresponding vertical columns in the two tables show 

 that the expressions by lichenists are nearly unanimously in favor 

 of maintaining the group Lichenes, while about one-fourth of 

 those by other botanists are favorable to abandoning the group. 



The first two rows of horizontal figures in the first table show 

 that while the lichenists stand very largely for the integrity of the 

 group, other botanists are much more largely in favor of main- 

 tenance for purposes of convenience than because they consider 

 the group a natural one. 



Further examination of the first table shows that besides the 

 arguments for maintenance expressed in the first three horizontal 

 rows of figures and already considered, the only other one noted 

 by a considerable number of botanists is that expressed in the 

 fourth horizontal row. Nine Europeans expressed this view 

 (that present knowledge is not sufficient to distribute) and only 



