145 



a question which would not be likely to iind any speedy solution in 

 response. 



With such examples before our eyes, we are bound to concede to 

 the transitionists, that plants do possess a capability of wide variation 

 from any one form which we may choose to select for the normal or 

 typical form of a species. But are these variations sufficiently wide 

 to give any probability that one species may pass gradually into ano- 

 ther ? As a reply to this query, I will now cite some few instances of 

 admitted species being tied together (so to speak) by a series of inter- 

 mediate forms. 



According to the usual application of the term, it may be safely 

 assumed that Geum urbanum and Geum rivale are two distinct spe- 

 cies. They are easily distinguished by several well defined charac- 

 ters ; and I do not recollect that any botanical authority has united 

 them under a single specific name. Yet intermediate forms between 

 them have long been familiar to botanical eyes, and which have usu- 

 ally been accounted varieties of one or of both the species above 

 named. These intermediate forms have been commonly clubbed to- 

 gether, under the single name of "intermedium;" this name meaning 

 a third species in the estimation of some few botanists, a variety in 

 that of most others, or a series of intermediate varieties in the eyes 

 and ideas of another and smaller section of botanists. The Geum 

 intermedium is taken up as a distinct species, by our present great 

 adopter and maker of dubious species, who writes, " If this plant is 

 not a distinct species I do not know to which of the others it should 

 be referred." There is, however, a strong objection against regard- 

 ing the plant as a " distinct -species," in the fact, that it is not one 

 clearly defined form, with characters intermediate between those of 

 two other well marked forms ; but that it is really a group or series of 

 intermediate forms, which run into Geum urbanum, at one end of the 

 series, while approximating also to Geum rivale at the other extremi- 

 ty. Apparently, both species sport into varieties ; and these varieties 

 run so near together as to have been combined into one supposed 

 third species. 



We obtain another familiar example in the cowslip and primrose. 

 Though some degree of doubt may have been expressed occasionally, 

 the prevailing opinion has clearly been, that Primula veris and Pri- 

 mula vulgaris are truly distinct species. They are so dissimilar that 

 every country-bred child can distinguish them with the greatest faci- 

 lity. They are extremely abundant in many places ; and thousands 

 or tens of thousands may be examined without any decided example 

 Vol. II. T 



