Multiplication of Extremes 763 



scription was given by Morren, and though 

 more than one varietal name is recorded in his 

 paper, it appears from the facts given that even 

 at that time only one variety existed. It was 

 commonly called Syringa vulgaris azurea 

 plena, and seems to have been very rare and 

 without real ornamental value. 



Lemoine, however, conceived the desirability 

 of a combination of the doubling with the bright 

 colors and large flower-racemes of other lilacs, 

 and performed a series of crosses. The 

 ' azurea plena " has no stamens, and therefore 

 must be used in all crosses as the pistil-parent ; 

 its ovary is narrowly inclosed in the tube of the 

 flower, and difficult to fertilize. On the other 

 hand, new crosses could be made every year, 

 and the total number of hybrids with differ- 

 ent pollen-parents was rapidly increased. 

 After five years the hybrids began to flower and 

 could be used for new crosses, yielding a series 

 of compound hybrids, which however, were not 

 kept separate from the products of the first 

 crosses. 



Gradually the number of the flowering speci- 

 mens increased, and the character of doubling 

 was observed to be variable to a high degree. 

 Sometimes only one supernumerary petal was 

 produced, sometimes a whole new typical corolla 

 was extruded from within the first. In the same 



