BIOTYPES AND HYBRIDS. 47 



(059.56) were sown November 1, 1906, and produced 24 plants, all agree- 

 ing" perfectly with the original type as described (fig. 22). These became 

 diseased later, however, and produced no seed. 



056.88 : This plant was considered a typical specimen of B. bp. simplex, 

 though a little more vigorous and broader-leafed than usual. It was care- 

 fully castrated and pollinated with pollen from a plant belonging' to my 

 first culture of B. heegeri (059). The seeds were sown April 25, 1906, and 



FIG. 22. Bursa heegeri. Second controlled generation. 



produced 108 offspring:, all resembling B. heegeri more closely than B. bp. 

 simplex, but they differed markedly from the former because of the imper- 

 fect dominance of the heteris characteristics . On this account these plants 

 had some of the characteristics of B. bp. rhomboidea and could be properly 

 described as intermediate between B. bp. rhomboidea and B. bp. heteris (fig. 

 23). A few of these died without seeding, but all that came to maturity 

 had the triangular capsules typical of Bursa bursa-pastoris . One family 

 was raised from unguarded seeds of one of these plants (0688.212), as 

 described below. 



