ON TRIPLE HYBRIDS. 



501 



as any other evening primrose. This enabled me to study the second 

 generation of the lata, wiiicii, in contrast to that of the laeta and the 

 velutina, repeats the splitting. The yield of the pollen was small in 

 the unfavorable summer of 1907, but large during the hot days of 

 July and August, 1908. 



I have made this cross twice, in 1905 and 1907; the parents were 

 annual specimens. I had the following results in the first generation: 



Here also the laeta and velutina were the same as those from the 

 cross with Lamarckiana. I sowed some self-fertilized seed of the 

 velutina of 1906, partly in 1907 and partly in 1908, and cultivated 

 from each lot 60 specimens, all of which repeated the velutina char- 

 acters. 



The lata specimens also were cultivated from seed of 1906 in both 

 succeeding years. Their flowers were as large as those of both 

 parents and intermediate in the tinge of the yellow, the Hookeri 

 being paler yellow than the Lamarckiana and its lata. The anthers 

 did not reach the stigma, which was often hand-shaped. The spike 

 was much denser than that of Hookeri but thinner than that of the 

 mother. Stem, veins, and calyx were reddish; and leaves were 

 narrower than in 0. lata. In all these and in other characters the 

 plants were strikingly lata, but with the addition of the differen- 

 tiating marks of the Hookeri. 



The self-fertilized seed of the lata plants of the first generation 

 gave a mixed progeny, consisting of velutina and lata, both resem- 

 bling the types of the first year. No laeta specimens were produced. 

 The numbers were the following: 



