92 HORTICULTURAL SOCIETY OF NEW YORK. 



wish to speak of the work by Macfarlane on the structure of certain hybrids, 

 a work published about ten years ago. After giving in detail the minute 

 structure of several hybrids, this author arrives at this general conclusion 

 concerning the nature of a hybrid, namely, that it is a blending of the char- 

 acters of the parents, each parent contributing equally to the offspring. The 

 hybrid is thus intermediate in structure between the parents. 



Although it may be at this time premature to suggest a relationship be- 

 tween the results of studies in the structure and those from experiment, 

 nevertheless it is interesting to note that practically all of the hybrids re- 

 ported by Macfarlane are of the intermediate type of Correns, and perhaps, 

 therefore, such results as INIacfarlane obtained might thus have been ex- 

 pected. From this the possibiHty is suggested that hybrids which are not 

 of the intermediate type may have a minute structure which is likewise not 

 intermediate. No work on this phase of the subject has yet been done, 

 however. 



Finally, as has already been stated in the foregoing summary of the re- 

 cent cytological work upon hybrids, this line of research and the experimental 

 have gone on independently of each other, but it may be reiterated here that 

 in order to better understand the causes of the variations in hybrids and 

 that of the differences in capacity for variability it is highly desirable that the 

 cytological and experimental work go hand in hand, that cytological work 

 be done on forms that give marked experimental results. 



