204 THE EVOLUTION OP OUR NATIVE FRUITS 



turists. It was a relief to have these anomalous forms separated 

 from Prunus Americana and from P. angustifolia, where they had 

 previously caused confusion ; and it was gratifying to have them 

 separately characterized, even though it was very difficult to 

 make the specific description fit all the varieties. But to main- 

 tain a description for the species which would fit all the varie- 

 ties has been an ever-growing puzzle. And thus a second time 

 Professor Bailey has brought us relief by his decision that this 

 is "a mongrel type of plums, no doubt hybrids" 



of Prunus Americana and P. angustifolia. 



This new view of the hortulana plums seems likely to find 

 much readier currency among pomologists than did the distinct 

 species view. Indeed, some reputable horticulturists have never 

 accepted the separate species notion ; and no two anywhere or at 

 any time have fully agreed upon the varieties which were to be 

 referred to the species. 



These cultivated varieties present an inextricable confusion 

 of closely graded differences of character passing without a 

 break from Prunus Americana, through the Miner group (Bailey's 

 P. hortulana var. Mineri), then through the Wild Goose group, 

 and by way of such varieties as Schley, Clifford and Macedonia 

 into the true Chickasaws. There is absolutely no line of demar- 

 cation, however dim, among these varieties. Such a series of 

 forms cannot be conveniently doled out into species, even when 

 we take the most advanced evolutionary view of what constitutes 

 a species. But as soon as the Wild Goose group is understood to 

 be a company of hybrids, the matter becomes comparatively clear. 

 We can easily believe that there have been numerous independent 

 hybrid origins followed by still more numerous secondary, ter- 

 tiary and quartenary crosses, and these would account fully for 

 the extraordinary variability and wide diversity of characters 

 among these plums. The varieties of the Miner group may rea- 

 sonably be supposed to be secondary hybrids between Wild Goose 

 types and Prunus Americans ; or they may be, in some instances, 

 primary hybrids in which the Americana influence has preponder- 

 ated. Such varieties as Ohio Prolific, Schley, Texas Belle and 

 Wooten may be supposed, on the other hand, to be secondary 

 hybrids between Wild Goose and the Chickasaws. 



All this will drive every plum student, pomologist or botanist 



