24 Latent and Scmi-Latcnt Characters. 



in which at least, in spite of every precaution and care, 

 I have not yet succeeded in obtaining the one race from 

 the other. (Trifoliiiui incarnatuni qiiadrifoluiui, T. pra- 

 tcnse quiuqiiefolium, Ranunculus bulhosus semiplenus.) 

 On the other hand are those races which when cultivated 

 on a sufficiently large scale give rise every year to indi- 

 viduals which seems to overstep the otherwise fixed lim- 

 its of the race. These are therefore inconstant inter- 

 mediate races. I regard this phenomenon as one of 

 atavism, at any rate in those cases where, as in my own 

 observations, they revert from an eversporting variety 

 to the type of the parent species without however ac- 

 quiring the constancy of the latter. Atavistic phenom- 

 ena of this kind are well known in striped flowers and 

 variegated leaves ; and I have also found very striking 

 examples of it in Linaria vulgaris peloria and Plantayo 

 lanceolata raniosa (§20 and § 17). 



Besides the cases which fall into the two categories 

 just discussed, I succeeded in finding a third in which one 

 intermediate race arose from the other very rarely and 

 only in isolated cases. I have seen two cases of this so 

 far. One was the origin of Linaria vidgaris peloria from 

 L. V. hemipcloria (§ 20); the other was the formation 

 of the double Chrysanthemum segetuni plenum (Plate 

 II), from C. s. grandiflorum with 21 instead of 13 

 tongue-florets (§ 18). Linaria vulg. peloria is probably 

 an intermediate race, on account of its inconstancy; 

 whereas L. vulg. hemipeloria (with stray peloric flowers) 

 is obviously a half race. The origin of the former from 

 the latter presumably occurs in nature from time to time. 

 My Chrysanthemum segetum plenum is a novelty in the 

 horticultural sense of the term, being just as double as 

 the double varieties of other composites; so far as I 



