86 University/ of Califoiitia PiibJications in Agricultural Sciences [Vol.4 



tabulation of parental data by italic figures, while protection possibly 

 defective will be indicated by an asterisk. It is not probable that 

 much vicinism occurred in the greenhouse cultures, since this plant 

 is well adapted to self fertilization. 



In the first year's (1906) cultures the plants in each experimental 

 environment were separately numbered. Each plant was designated 

 by its number preceded by two letters indicative of the environment. 

 For greenhouse temperature these letters were C (cool), M (medium 

 temperature), and W (warm) ; for potting soiP they were S (sand). 

 L (unfertilized "loam"), and G ("good" soil, fertilized). Thus CSl 

 CS2, WG9. etc., were pedigree numbers of the first generation, and 

 CG2-M8 and WG9-C10 of the second generation. A few syncotyle- 

 donous plants outside the regular cultures of 1907 were called WG9- 

 synl, etc. 



For the work at Riverside a new system of numbering was adopted, 

 better suited to ordinary pedigree cultures, and the numbers from 

 this system are used below in the individual treatment of all but one 

 of the mutant .types ("early"). This is essentially Webber's (1906, 

 p. 308) system, except that each initial or Pj individual of a series is 

 indicated by a letter; a full description has been published (Frost. 

 1917). With MaWiiola each type or cross between two types that is 

 tested receives a series number, the apparent mutants themselves 

 always being taken as the initial individuals of their selfed series. 



The cultures of 1908 included progeny of various parents, one being 

 WG9-C10. an early and few-noded plant suspected of being a mutant. 



The cultures of 1910 consisted of a second-generation test of WG9- 

 ClO, and a first-generation test of other possible mutants, with control 

 lots. The plants were all grown on one bench in one greenhouse 

 (house C), from thirty lots of fifteen seeds each, lots 1-17 relating to 

 WG9-C10. The parents descended from WG9-C10 (see table 7) were 

 selected as those with fewest internodes, a medium number of inter- 

 nodes, and most" internodes in each house of the 1908 cultures, earli- 

 ness of flowering being considered when parents were alike in number 

 of internodes. The control parents were both few-noded and many- 

 noded, relatively to their sibs. 



In 1911 eighty progeny lots were grown in the field at Ithaca. 

 Lots 1 to 28, transplanted from the greenhouse, paralleled the test of 



•"'Soil experimentally varied only in the 1906 cultures, temperature varied in 

 the two following years also. 



"For house M, not the highest, which was exi;'eptionally high, but the next 

 to the highest. 



