Manchester Memoirs, Vol. Ivi. ( 1 9 1 1 - 1 2 ). 5 



hold good for a stiil greater variety of characters in an 

 extensive series of plants and animals. 



De Vries, who was one of the first to draw attention 

 to Mendel's work, took for one of his experiments the 

 interesting cut-leaved variety of the Greater Celandine, 

 Chclidonimn viaj'us var. lacimatiun, which is said to have 

 appeared suddenly as a sport in the Botanical Gardens of 

 a pharmacist in Heidelberg in the year 1590. This 

 interesting form is characterised by the laciniate condition 

 of its leaves and petals. When pollinated with pollen of 

 the normal form it produces a hybrid which is hardly 

 distinguishable from normal plant. In the second hybrid 

 generation, however, 25 % of the plants are found to revert 

 back to the type of the cut-leaved maternal parent 



During the past summer I have repeated this experi- 

 ment of De Vries and obtained 209 recessives and 612 

 dominants. They are easily recognisable even in the 

 seedling condition by their more deeply cleft leaves and 

 the rather sharper teeth of the margin (see Figs, i and 2). 

 De Vries also showed that if the hybrid is pollinated with 

 the pollen of the recessive laciniate parent, the numerical 

 ratio of dominants and recessives is 2:1, as would be 

 expected from the Mendelian hypothesis. It is of interest 

 in connection with this example of Mendelian inheritance 

 to note that the original form is dominant over the more 

 recent sport, the cut-leaved form, and though not 

 without exception it is found very generally that the 

 more ancient form is dominant to the newer variety. 



An interesting case of colour inheritance has occupied 

 my attention during the past two years, and offers a very 

 striking illustration of the Mendelian laws of inheritance. 



A well-known variety of the common Pimpernel 

 {Anagallis arvensis) bears bright blue flowers, which are 

 in strange contrast with the scarlet flowers of the normal 



