232 Non-Isolabic Races. 



cogo liipuliua, whilst Braun has observed them In M. 

 safk'a. They are well known in T. pratcnsc and T. 

 rcpeus, and Wydler has recorded 4-foliate leaves in 

 Lotus major and Tctragonolobiis biflonis. In some suc- 

 cessive sowings which 1 made with Medicago lupulina I 

 found the character to be inherited although in a mod- 

 erate degree only, but I have not continued the experi- 

 ment. 



But let us return to the crimson clover. The question 

 is, what prospects were present at the beginning of the 

 ex])eriment, and what may be expected from such ex- 

 periments in general ? There are three main possibilities 

 to be considered. We may find at the beginning of the 

 experiment (See § 3 p. 20) : 



1. A race which often exhibits the anomaly in ques- 

 tion, and bears it as a heritable character, i. e., an ever- 

 sporting variety; 



2. A half-race with a semi-latent anomaly v/hich is 

 only occasionally manifested; 



3. An ordinary plant of the species with the character 

 in question in a latent condition. 



In the first case the race already exists and all that 

 is necessary is to isolate it ; in the second it may possibly 

 be obtained : in the last there is little prospect of doing so. 



In order to present a clearer idea of the mutual rela- 

 tions of these three cases let us examine TrifoUuui repens 

 and T. pratense. That the anomaly is by no means A-ery 

 rare is testified in both cases by the popular belief in the 

 so-called lucky four-leaved clover as well as by common 

 experience. If looked for in a field of clover, or in a 

 meadow, or along the roadside, a four-leaved clover will 

 be found from time to time. If repeated attempts are 

 made to find them they will certainly prove to be rare 



