196 Varietäten, Descendenz, Hybriden. 



tements of Statistical relationships. The differences usually measured 

 by the biometricians "coefficient of Variation" are thus seen to be 

 devoid of significance for selection or evolution. The changes on 

 which selection can act are comparatively rare. Further. the diffe- 

 rences between genotypes, however they may have arisen, are 

 very small, going down to the limits of exact measurements, so 

 that an important question is raised, as to the meaning of genotypic 

 differences. Gates. 



Keeble, F., Miss C. Pellew and W. N. Jones. The Inheritance 

 of Peloria and Flower-colour in Foxgloves {Digitalis 

 piirpurea). (New Phytologist. IX. p. 68—77. 1910.) 



The peloria in the examples studied is confined to the terminal 

 flower of the raceme, which is bell-shaped and Stands erect, thus 

 forming a striking contrast with the pendulous zygomorphic lateral 

 flowers. The peloric State is recessive to the normal, and it is 

 noteworthy that the offspring of peloric plants selffertilized all 

 possess the terminal peloric flower, whether the seed be obtained 

 from the lateral zygomorphic flowers of the parent or from the 

 terminal peloric flower. 



The colour characters which have been investigated are the 

 colour of the coroUa and the presence of red, brown and yeliow 

 spots on the corolla tube. 



Certain white plants, when selfed, have given offspring con- 

 sisting of whites and magentas; Foxgloves may therefore contain 

 an inhibiting factor which gives rise to a Dominant White. Experi- 

 ments with another white plant suggest that it was probably a 

 recessive white, lacking the factors necessary for the production 

 of colour in the flower. 



The behaviour of the red and yellow-brown spots appears to 

 admit of a simple Interpretation. It appears that red spots occur 

 only in plants which contain the factor for magenta flower-colour. 

 Thus, so far as is known, all magenta flowers have red spots; 

 whites, on the other hand, may have either red or yellow-brown 

 spots. Whites with red spots are dominant whites containing the 

 factor for flower-colour; whites with yellow-brown spots ma}^ be 

 dominant whites which lack the factor for flower-colour, or recessive 

 whites. It is suggested that the differential action of the dominant 

 white factor-inhibiting the ground colour but not the colour in the 

 spots, may provide a clue to the behaviour of such striped types as 

 are known to produce, occasionally, self-coloured offspring. 



R. P. Gregory. 



Klebs, G., Alterations in the Development and Form of 

 Plants as a result of Environment. Croonian Lecture de- 

 livered before the Royal Society. (Roy. Soc. Proc, Ser. B. 

 LXXXII. p. 547—558. 1910. Abstract in 'Nature'. LXXXIII. 2118. 

 p. 414. 1910.) 



In illustrating the alterations in the development of plants which 

 may be brought about by appropriate conditions of environment, 

 Prof Klebs described some of his well-known experiments, selecting 

 Saprolegnia as an example among the lower plants, and Sempervi- 

 vum among the higher plants. 



The transformation, in Senipervivutn, of rosettes "ripe to flower" 



