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THE AMERICAN NATURALIST [Vol.XLIV 



with leaves that are coarsely toothed at the base, and col- 

 onies of V. sagittata with decidedly pubescent leaves ; in- 

 deed, this is the prevalent form in the middle west. 

 Where the two species grow together, these and various 

 other interchanges of characters are frequent, in accord- 

 ance with Mendelian principles of segregation. A like 

 interchange of characters is noticeable in the stemless 

 white violets, V. blanda, V. renifolia and V. incognita; 

 and also in the stemmed yellow violets, V. pubescens and 

 V. scabriuscula. 



We often find in species of wide distribution, as for 

 example V. affinis or V. papilionacea, numerous forms 

 distinct in one or more characters. Those who are so in- 

 clined can break up any one of these species into a dozen 

 or more 1 1 elementary species," as some European botan- 

 ists have done with V. tricolor. But there are also cer- 

 tain species of Viola that are not polymorphic though of 

 fairly wide distribution; for example, V. rotundifolia, V. 

 Selkirkii, V. hastata; and it is worthy of note as bearing 

 upon the thesis of the present paper, that these species 

 have never been found to hybridize. 



It frequently happens that a subhybrid form in Viola 

 is so unlike either parent of the first-cross as to appear to 

 be specifically distinct. Many such violet hybrids have in 

 recent years been named and published as species: V. 

 Mulfordce Pollard, V. notabilis Bicknell and V. aber- 

 rans Greene are examples. It is surely hazardous in our 

 present knowledge of the genus to put forth as a species 

 a newly discovered form of Viola, without studying it 

 through at least one season of growth and through one 

 generation of offspring. It may, indeed, transpire that 

 the new form, though of hybrid origin, is distinct and 

 stable; and if fairly wide-spread, it may be entitled to 

 specific or varietal rank. The bar sinister in the escutch- 

 eon of its bastard ancestry may have been quite oblit- 

 erated. We may be here witnessing the birth of a new 

 species through hybridism. Allow me in closing to pres- 

 ent an instance that makes a close approach to these con- 

 ditions. 



