148 



there is a gradual transition or series ranging from the ordinary 

 cowslip into the Claygate Oxlip, or even a little nearer to the caules- 

 cent primrose than is the latter. Placed in groups, they may stand 

 thus : — 



10 Primula veris, most of them with flowers larger than usually 



seen in the wild cowslips of the meadows, a difference which 



may be attributed to the vigorous growth of young plants 



unimpeded by other roots around them. 

 2 Primula veris var. major, differing from the true cowslip by 



their larger and flatter corollas, paler in colour, and by the 



more acute teeth of their calyces. 

 4 Primula vulgaris var. intermedia ; the flowers more like those 



of the primrose than those of the cowslip, in colour, size, 



and form. 

 In connexion with the previously recorded experiments, 1 seem 

 now to be justified in asserting; first, that seeds of a cowslip can 

 produce cowslips and oxlips ; and secondly, that seeds of an oxlip can 

 produce cowslips, oxlips, and primroses. The transition from the 

 cowslip (P. veris) to the primrose (P. vulgaris) is thus complete, but 

 not direct or immediate ; for, I have not yet ascertained that a typical 

 P. vulgaris can produce a typical P. veris, or vice versa, without 

 passing through or producing the intermediate link of the oxlip, 

 namely, the P. vulgaris var. intermedia of the ' London Catalogue,' 

 and several times mentioned in the ' Phytologist,' under name of the 

 " Claygate Oxlip." 1 employ the term oxlip to designate the inter- 

 mediate form, because it is undoubtedly to that variety of primrose or 

 cowslip, or hybrid of both, that rustics apply the name : they do not 

 intend Jacquin's P. elatior, the Bardfield Primula, under a name which 

 is familiar in various counties. 



It may here be observed that, in my own experiments, the seeds 

 have always been taken from a single plant, examined and marked 

 while in flower, and dried examples of it preserved in my herbarium ; 

 so that, whether a typical form of cowslip, or a variety of oxlip, I am 

 able to point out the parent or its counterpart exactly. In a former 

 volume of the 'Phytologist' (i. 218 and 313) I mentioned that the 

 antecedent experiments wanted one or other of these requisites of 

 precision ; and it therefore appears to me to be still a desideratum, to 

 show by experiment that a primrose can produce a cowslip, or a cowslip 

 produce a primrose, directly at the first descent, without an intermediate 

 stage of the oxlip form. The hybridization hypothesis would be ne- 

 gatived by the crucial experiment of this direct production or change. 



