gp:netic studies in polemonium coeruleum 



dites raised from crosses between females and hermaphrodites; 

 see Table 2. 

 f. On the other hand self-fertilized true hermaphrodites give 

 either only hermaphrodites or very few females: 



1. A blue hermaphrodite was self-fertilized in 1917, the off- 

 spring was 12 hermaphrodites and one of these (No. 500 a) 

 gave an F2-generation of 59 hermaphrodites. See also the 

 Exp. 1 a and b. 



2. A white hermaphrodite was self- fertilized in 1917; tlie off- 

 spring was 40 hermaphrodites and 2 females. 



These results agree in the main with e. g. Ralnki.kiî's studies 

 in Thymus vulgaris and KnautUt arvensis. 



We may generalize the results hitherto obtained in the lollcnv- 

 ing way: 

 By crossiny females with hermaphrodites the offspriny is mainly 

 female with few (9,5 % §) hermaphrodites. The intermediate types 

 give an offspring of more females than hermaphrodites (34 % §), and 

 the true hermaphrodites give mainly hermaphrodites {ca. 99 % ^ ) with 

 very few females. 



g. It was mentioned above (p. 21) that in the micropetalous form 

 we had either hermaphrodites or abnormal females with no 

 trace of stamens and without power to be fertilized. 



The offspring of the original micropetalous plant referred 

 to in 2 a consisted of 3 hermaphrodites and one abnormal female. 

 The three hermaphrodites gave after self-fertilization respec- 

 tively 28 ^ 9 ? ; 7 ^ 5 $ and 9 ^ 3 $, in total 44 § and 17 $. The 

 result shows more females (28 % ?) than when self-fertilizing 

 true hermaphrodites of the normal type. 



From this short report it appears, I think, that the forms of Pole- 

 monium coeruleum exhibit many interesting problems, but also that 

 the studies are only at the beginning. I hope to be able to continue 

 them, and in a larger scale. 



LITERATURE CITED. 



1. HuANi). A. 1U07. Polonioniaceae. in Das Pflanzonreich. IV. 2.')0. 



2. CoKHENS, C. 1904. Experimcniello rnlcrsuchungen über Gvnodioccie. Ber. 



Deutsch, bol. Gesellsch. 22. 



