MISSO^ 

 BOTANIC^ 

 GARDEN. 



A.NALOG1ES AND AFFINITIES. 



III. 



In preceding; articles, I have here and there alluded to this 

 circumstance : tliat systematic botanists whose theories of 

 classification exclude the consideration of odors and flavors 

 of plants, do nevertheless in practice now and then resort to 

 them, and press them into service, for the more prompt recog- 

 nition at leastj if not for the more satisfactory delimitation 

 of species, genera and orders. 



Some telling examples of this occur in the history of the 

 genus Allium. "Within it are now comprised, according to 

 tlie limits set to it by all authors now living, plants of 

 extremely wide and varied organographical differences; such 

 degrees of difference as are not allowed within one genus in 

 any other tribe of endogenous plants. And while this is 

 true, there are others formerly retained in Allium, which are 

 uow excluded from it, not because of any morphological dis- 

 agreement whatsoever, but solely on account of their lacking 

 what is known as the alliaceous odor and flavor. 



Let us note, first of all, some of the more important and 

 striking diversities of organic structure which the genus, as 

 now received, exhibits. There are leaves' narrowly linear and 

 fiat ; leaves broad and carinate-complicate ; leaves terete and 

 solid ; leaves terete and hollow. In this order of the vege- 

 table kingdom, it is usual to found genera upon such dis- 

 tinctions as these ; as also upon the character of scapes, as 

 flattened and sharply two-edged ; as terete and solid, or as 

 terete and hollow; but the genus Allium is, as though by 

 special license, permitted to include all these diversities 

 of flower-stalk. As to the perianth, there are some sorts 



PiTTONIA, Vol. II. 



Maj 1, 1890. pp. Sl-T'i 



