The genus Alcicornium of Gaudichaud 



LuciEN Marcus Underwood 



The adoption of 1753 as the initial date for botanical nomen- 

 clature in the Rochester rules of 1892, ratified by the Genoa 

 botanical congress in the same year, reiterated by various botani- 

 cal organizations down to the present year, and now almost uni- 

 versally accepted by botanists, settled a supplementary but more 

 fundamental problem which had hitherto been an obstacle to the 

 progress of a correct understanding of genera. The principle thus 

 established is briefly stated as follows : A genus is a group of 

 closely related species and not a definition. The converse view of 

 this principle has led to untold misconceptions in regard to a pro- 

 per understanding of what genera really are, particularly among 

 the ferns. If a species has no near relations it will form a mono- 

 typic genus concerning whose nomenclatorial type there can be no 

 question ; nevertheless, in the practice of the past, generic names 

 of this sort have often been passed along from the original mono- 

 type to species later added, until in their present acceptance they 

 would not be recognized by their founders. Linnaeus' Species 



t> 



loses of genera, and as a necessary 

 corollary, a genus may be founded at any time by giving a generic 

 name to a species or group of species. Such a genus is ''rite 

 published/' to quote an expression from an author on whose re- 



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strictions this article is in part a protest. Botanical literature has 

 frequent examples of such publications, of which I cite a single 

 one which has recently been accepted without question : 



In an *• observatio" appended to the description of the genus 

 Bolbitis, Schott (Gen. Fil. //. 14) says : '' Praeter Bolbitin alia duo 

 genera : Elaphoglossum et Rhipidopteris, ab Acrostichis genuinis 

 sunt segreganda. Prioris generis exempla sunt : E. simplex, con- 

 forme, apodum, viscosum, vestitum, etc. (Acrost. simplex, con- 

 forme etc. Auctorum); posterioris * * */' (1834-) 



This is the proper starting point of the genus Elaphoglossum, 

 and no one has seemed to take the gerundive construction in any 

 other way than an intention on the part of the author to here 

 establish a new genus. A few years earlier Gaudichaud, in the 



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