Greek and Latin in Biological Xomenelatitre 7 



identical in meaning and essentially so in derivation. They are 

 to be regarded merely as dilTerent forms of the same compound, 

 and Calothrix becomes a homon}m. The confusion wrought by 

 alternative forms and blundering construction is nowhere better 

 shown than in the following series of names, belonging to five 

 different genera: Asterothrix Cassini 1827 (Asterotrix Brogn. 

 1843, Asterothria Gren. 1850), Asterotrichion Link 1840 (As- 

 terostrichion "Klotsch" 1840, .Vsterotrichium Witts.), Astero- 

 trichia Zanard. 1843 Astrotricha DC. 1829 (Astrotrichia Rchb. 

 1837), and Asterotrichum Bonord. 1851. 



The retroactive application of this rule is imperative for the 

 sake of uniformity and purity. By far the greater number of 

 plant genera have already been recognized and named. The new 

 names to be proposed for years to come will be relatively few, 

 and a reform which affected even all of these would be barel\' 

 worth while. Further than this, most new names are made after 

 the pattern of names already in use, whether correctly or incor- 

 rectly formed, a practice certain to perpetuate the blunders of 

 the past. Arguments from the standpoint of purity are equally 

 cogent, but, as they would perhaps appeal to the philologist alone, 

 they will not be insisted upon here. A rule of this sort to be at 

 all worth w'hile must be retroactive, for by retroaction alone can 

 confusion be avoided and uniformity secured. The retroactive 

 operation of the rule must be so safeguarded, how^ever, that 

 changes for reasons of uniformity or purity will be made upon 

 real and not upon supposititious grounds. Framers of generic 

 names have been extremely careless in the matter of indicating 

 etymologies, but this is riot sufficient warrant for reconstruct- 

 ing names upon the basis of supposed meanings. Alany a genus 

 has received a name of known or evident etymology, but of 

 meaningless or mistaken application, a fact which should re- 

 strain us from correcting words of unknown derivation on the 

 basis of an assumed etymology. In making changes to secure 

 •a more uniform and stable nomenclature, the greatest care must 

 be taken to minimize the error arising from personal judgment. 

 In many words of uncertain etymology, several derivations are 

 equally plausible, or at least possible, and the exercise of per- 



327 



