88 proceedings: botanical society 



standing which they produce an abundance of seeds. These seeds 

 originate parthenogenetically and represent a pure strain of the female 

 parent. But in some few cases there is a true second generation. 

 The individuals of the first generation vary greatly. The fruit may be 

 smaller than that of either parent, or larger than the combined fruits of 

 the two parents; it may be smooth or hairy, lemon-colored or orange- 

 colored, with a great profusion of oil glands or almost without any; the 

 shape of the tree may vary; the leaves are often 5-foliolate, although one 

 parent is unifoliolate and the other always 3-foliolate. There is a very 

 considerable cohesion of characters in the second generation of Citrus- 

 Poncirus hybrids. It seems all but impossible, however, to secure hard- 

 iness and an orange flavored fruit at the same time. In the case of 

 Citrus-Poncirus hybrids great vigor is observed in the first generation. 

 If this first generation is crossed with a kumquat, increased vigor also 

 is shown; but no increase in vigor results from the return cross between 

 the first generation and the parental species. The kumquat belongs 

 to a distinct genus, Fortunella, so that in crossing a citrange with a 

 kumquat a trigeneric hybrid is produced, combining Citrus and Pon- 

 cirus with Fortunella. Although the kumquat is a dwarf plant, its 

 diversity from Citrus and Poncirus is so great that when crossed with 

 a citrange it brings about greatly increased vigor. By crossing Pon- 

 cirus trifoliata with the ordinary orange, and then crossing this first 

 generation hybrid with the kumquat, a fruit somewhat resembling the 

 lime has been produced; it has no direct genetic relationship with the 

 latter, however. 



During the general discussion Mr. L. C. Corbett and Prof. William 

 Stuart discussed the behavior of carnation hybrids, and the latter 

 called attention to the desirability of securing as high a percentage of 

 germination as possible in the second generation, in order that no selec- 

 tive error be introduced into percentage determinations. Mr. Norton 

 said that of several thousand cases of carnations grow n from commercial 

 types, the percentage of singles never was higher than 23 per cent. 



H % L. Shantz, Corresponding Secretary. 



