219 



could have been in the soil used in the tlower-pot. But whence the 

 connecting series of varieties in that case ? 



According to the technical idea of a species, which makes it em- 

 brace all individual examples which have (or might have) descended 

 from a common progenitor, all my plants — whether cowslips, prim- 

 roses, or varieties of either — must belong to one single species ; and 

 thus we fall back upon the Linnean notion of one " Primula veris," 

 with its subordinate varieties of " elatior " and " acaulis." This view 

 will scarce find favour in the eyes of those botanists who labour un- 

 der the " species-splitting " monomania. The wild cowslip and 

 primrose have well-marked characters for distinction, and characters 

 which are usually very regular and constant. So far they are now 

 dissimilar, and more constantly dissimilar, than are numerous pairs 

 of " book-species," which are unhesitatingly received as really dis- 

 tinct in nature. Unite plants so dissimilar and so readily distin- 

 guished, as are the cowslip and primrose, — and what are we then to 

 say about the frivolous attempts at species-making among the Rubi 

 and Polygona in vogue at present, as among the Rosae and Menthae 

 in former years ? 



If we allow the cowslip and primrose to be two species, and yet 

 allow that one can pass into the other, either directly or through the 

 intermediate oxlip, we abandon the definition of species, as usually 

 given, and fall into the transition-of-species theory, advocated in the 

 * Vestiges.' 



I do not see that we get more clear of the difficulty by assuming, 

 without proof thereof, that the " Claygate oxlip " is a true example of 

 hybridity. Do hybrids, if fertile, produce at once their own like, 

 the like of each parent, and a progeny of intermediate likeness also ? 

 At best, the hybrid is only half of either species, — and can the half 

 produce the whole ? Such an event would assuredly not be " like 

 producing like " through an endless succession of descents ? 



Let a few other cases be adduced, between reputed species equally 

 dissimilar, and we shall be forced to recast our ideas and definition 

 of the term " species." It would unavoidably become arbitrary and 

 conventional ; with no more exactness or constancy of application, 

 than we can give to the terms " genus " or " order." 



Hewett C. Watson. 

 Thames Dilton, June 18, 1845. 



