20 



The burden of proof that such is the case rests with those who hold 

 such views, and until satisfactory proof of the existence of these 

 elusive characteristics is brought forward, one may be pardoned for 

 looking upon such views as too indefinite to be utilised in systematic 

 work. We must fall back upon what we can readily test with our 

 senses. 



From an economic point of view it makes no difference that I can 

 see, in the matter of the ripe rots of fruit, whether there is only one 

 species capable of living on all sorts of fruit, or whether there are as 

 many species as there are kinds of fruit, each so like the others that it 

 is hardly possible to make a distinction, and each moreover able to 

 effect an entrance into all other kinds of fruit and produce rot. The 

 economic precautions required are the same in either case. From a 

 scientific point of view, however, the question is an important one, and 

 it is this fact that has led to this rather lengthy discussion. 



One is almost tempted to declare that species-making sometimes 

 becomes a kind of mania, that altogether flimsy and whimsical, not 

 to say unreasonable, differences have been seized upon as excuses for 

 adding unnecessary descriptive matter to scientific literature. If we 

 find that a particular kind of oats growing on sterile and sandy soil 

 exhibits a dwarf growth and a yellowish colour, we do not immediately 

 regard it as a new form, not forgetting to name it and announce the 

 discovery. Let us congratulate ourselves ! For it is not always thus 

 among our scientific friends. Is a fungus species newly found on a 

 peach ? Call it new and name it pruni. Same genus on the grape ? 

 Call it new, name it ampelinum. On the apple ? New, call it mali. 

 On banana ? Christen it musae. 



What next ? Sparrow in a pear-tree, Passer pyri ? 



The question may be less trivial than it seems. The different shades 

 he may assume in the green shadow of pear leaves, his different 

 attitudes due to the steepness of the pear twigs, the shape of his nest 

 consequent on the angle of the forks-: these are matters in the case 

 of the sparrow somewhat on a par with the characteristics to be noted 

 in the growth of a fungus merely as a consequence of happening to 

 alight on a pear. 



A reasonable allowance for the influence of environment would 

 prevent much confusion. It is not as if we were still in ignorance of 

 methods of cultivating fungi, and were obliged to rely upon specimens 

 as ordinarily found in nature. 



. Our criminal courts have learned some valuable lessons in identifi- 

 cation, and they long ago gave up trying to identify a criminal 

 by his name, knowing full well that the next time he comes before 

 them it will very likely be under a new "alias." The " rogue's 



fallery" is a safer source of information than any criminal list. " What 

 oes he look like ?", not " What is his name ?", is the question of the 

 expert. Measurements, photographs, indelible marks, these are the 

 reliable data. 



If this is so in the face of all our legally enforced registration of 

 names, it is certainly calculated to make us pause before putting too 

 much reliance on a mere name. 



