100 PLANT HYBRIDlZx^TION BEFORE MENDEL 



cum X ^^ orange Azalea he had never raised seedlings beyond 



the third or fourth leaf. From Rhododendron canadense X Azalea 



pontica, he succeeded in saving "only one out of more than a 



hundred seedlings, and that became a vigorous plant." (jh., 



p. 11.) 



He says further : 



"In these cases I apprehend that, although the affinity of the juices is 

 sufficient to enable the pollen to fertilize the ovule, the stimulus is in- 

 sufficient, the operation languid, and the fertilization weak and inade- 

 quate to give a healthy constitution. It has been generally observed that 

 hybrid fertilization is slower than natural fertilization, and that often a 

 much smaller number of ovules are vivified." (p. ii.) 



Herbert comments shrewdly on Knight's report as to having 

 "given at the same time the curl of one cabbage and the red color 

 of another to a third variety." (p. 12.) This Herbert considers 

 to have been impossible, if it was supposed to have been effected 

 by one fertilization. 



"He might easily have obtained the twofold features by two successive 

 crosses, but I believe not in one generation by simultaneous application 

 of different pollens : for I do not think that two grains even of the same 

 pollen can get effectual access to the foramen of one and the same 

 ovule." {ib., p. 12.) 



Herbert did much work, both of a systematic sort and by way 

 of crossing, upon the Amaryllidaceae, the species chiefly utilized 

 belonging to the genera Hippeastrum, Crinum and Hymenocallis^ 

 the genus Narcissus being also rather extensively dealt with. In 

 December, 1819, Herbert made a communication to the Horticul- 

 tural Society of London (Vol. 4, pp. 15-50), entitled "On the 

 production of hybrid vegetables ; with the result of experiments 

 made in the investigation of the subject," in which a number of 

 observations are made of some genetic value. For the most part, 

 the article consists of an account of various interesting crosses 

 with a number of genera of ornamental bulbous plants, together 

 with some discussion of the species question, and of the fact of 

 sterility in certain crosses. The case is reported of a cross by 

 Knight, between a smooth cabbage (female) and a curled and 

 red cabbage (male), in which the curled leaf character and the 

 red color both appeared in the seedlings. The state of knowledge 

 concerning fertilization is indicated by Herbert's discussion of 

 the subject. Seeds originally exist in the "germen." During the 

 maturation of the stigma, the germen and seeds grow until the 



