306 



THE AMERICAN NATURALIST [Vol. XL VI 



TABLE I 



Values of the Selection Index Number fob a Series of Plants of 

 Morse's Old-fashioned Yellow Eye Bean, together with the 

 Variables on which the Index Depends 















87* 



61 

 98 

 95 



62 



n 



80 

 89 

 55 

 69 



56 

 75 



60 

 78 



67 



79 

 73 



.79 



L37 

 1.51 

 1.56 



2^08 

 2^92 

 3.43 



:K 



4^7 

 5.35 

 5.51 

 7.32 

 7.37 



8.47 

 8.79 



•♦"on 



10.38 

 15.30 

 17.04 



5.5 gms. 



10 

 15 

 7JS 



12 

 16.1 



24.5 

 18 

 20.5 



19.5 

 30.9 



39 



27 

 26 



30 

 23 

 26 

 30 



38 



45.83 

 36.36 

 41.67 

 50.00 

 41.67 

 56.40 

 54.17 



49.53 

 50.97 

 57.64 



52.58 

 59.38 

 59.99 



59.10 

 59.42 

 51.10 

 59.99 



59.99 

 61.16 

 55.07 



63.17 

 52.88 

 59.10 



62^50 

 60.31 



2.00 

 3.90 

 3.43 

 3.77 



2.73 



4^33 

 3.58 

 3.47 

 2.87 



3^69 

 3.73 



3.33 



to7 

 3.18 

 3.42 

 3.59 



3.68 



3^67 

 5.42 

 3.48 

 3.89 



.50 

 .39 

 .58 



A3 



!56 



.42 

 .57 



.57 



A7 

 .51 



146 

 .34 



.43 

 .42 



5 1 60.00 



7 ! 62^50 

 13 41.45 



15 57J7 



12 54^03 

 9 64.10 

 12 67.44 

 15 55.98 



15 69.77 



16 69^9 



11 75.61 

 7 84.00 



12 77.50 



18 58.97 



17 70.13 

 27 55.86 



19 80.38 



17 82.06 

 16 87.04 



21 80.97 

 14 84.48 

 19 86.59 



22 84.06 



18 98.48 



pea bean. Table II gives the index and component variables 

 for a series of plants of such a variety. 



The range of values here is large. The extremely high values 

 are probably much larger than will ever be obtained for a bean 

 of the yellow eye type, though it is rather risky to make such 

 a prophecy. Two factors help in reaching such high index 

 values in the case of this variety. One is the tendency to prolifi- 

 cacy, there beinir tvlatiwh- many pods per plant and beans per 

 pod. The other is the rather high disease resistance of the 



* Plant injured by cut worms. 



♦Plant injured by cut worms, but subsequently grew. 



