210 THE QUANTITATIVE METHOD IN BIOLOGY 



as a characteristic of the genus. I have found the following 

 variation curve : — 



Number of nerves : 3456789 

 „ glumes : i o 12 3 i i i 



It is seen that the primordium under consideration is very- 

 variable ; that the figures 5 and 6 are predominant, and that 

 3 is a rarity ! 



Similar examples are found in UNLIMITED NUMBER in 

 the best systematic works in which Phanerogams, Fungi, Algae, 

 Fishes, Birds, Articulate animals. Shells, etc., are described.^ 

 As soon as we measure a few primordia in a sufficient number of 

 specimens of a species ^ and compare the result with the in- 

 formation given in a flora or a fauna, we discover vagueness, 

 inexactitude and even manifest errors. (See § 52.) 



I point out here a serious evil which seems to have been 

 hitherto overlooked.^ The systematists, confined in an anti- 

 quated routine, are the first victims of their deplorable method. 

 Since the great majority of the existing specific and even generic 

 descriptions are superficial and unfinished to such a degree that 

 the exact identification of a specimen is simply impossible, the 

 systematists discover continually and describe under new names 

 so-called new species, which have already been described either 

 once or even several times. The result is a complicated 

 synonymy and a discouraging disorder. When anyone tries 

 to make a catalogue of the flora or fauna of a given area, he is 

 faced with inextricable difiiculties. If he takes the pains of 

 travelling from one museum and private collection to another 

 in order to examine and to compare the types, he discovers 

 that numerous descriptions have been based upon one or two 

 specimens, or even upon a fragment, and he is again and again 

 disappointed.* 



Moreover, the existing descriptions are ordinarily very in- 

 complete. Only a few characters are mentioned, according to 

 a sort of conventional scheme, which would possibly have been 

 sufficient (or thereabout) a century ago, when the number of 

 known species was comparatively smaU, but which does not 

 answer the needs of modern science. The fruits and the seeds 



1 See other examples in my paper on Mnium. 



" Taking a species the identification of which is beyond any doubt. 



'See C. G. LLOYD, The Myths of Mycology, Part I. Cincinnati, 0. 

 (December, 1917). i6 pages.1 



The author of this paper has illustrated, by a number of examples, the 

 almost incredible imperfection of many well-known works on fungi and 

 the deplorable disorder which prevails in this department of descriptive 

 botany. 



« I repeat here in a few words what I was told by TH. DURAND, one of 

 the authors of Conspectus Floras Africance. 



