218 THE ORIGIN OF SPECIES 



actcr, however imjiortant that may Ix', has always failed; 

 for no ])art of the organization is invariably constant. 

 The importance of an aggregate of characters, even when 

 none are important, alone exi)lains the aj)horism enunci- 

 ated by LinnaBus, namely, that the characters do not give 

 the genus, but the genus gives the characters; for this 

 seems founded on the appreciation of many trifling points 

 of resemblance, too slight to be defined. Certain plants, 

 belonging to the Malpighiacese, bear perfect and degraded 

 flowers; in the latter, as A. de Jussieu lias romarlced, 

 "the greater number of the characters proper to the 

 species, to the genus, to the family, to the class, dis- 

 appear, and thus laugh at our classification." When 

 Aspicarpa produced in France, during several years, 

 only these degraded flowers, departing so wonderfully in 

 a number of the most important points of structure from 

 the proper tj'-pe of the order, yet M. Richard sagaciously 

 saw, as Jussieu observes, that this genus should still be 

 retained among the Malpighiacege. This case well illus- 

 trates the spirit of our classifications. 



Practically, when naturalists are at work, they do not 

 trouble themselves about the physiological value of the 

 characters which they use in defining a group or in 

 allocating any particular species. If they find a character 

 nearly uniform, and common to a great number of forms, 

 and not common to others, they use it as one of high 

 value; if common to some lesser number, they use it as 

 of subordinate value. This principle has been broadly 

 confessed by some naturalists to be the true one; and- by 

 none more clearly than by that excellent botanist, Aug. 

 St.-Hilaire. If several trifling characters are always 

 found in combination, though no apparent bond of con- 



