-o The Ottawa Naturalist. m 



selves with reproducing diagnoses that have been published 

 long ago, instead of submitting the plants to a renewed study, 

 whereby surely some new characters would be discovered ; the 

 only thing"" new" to be found in such systematic works seems to 

 consist in nomenclatorial changes : new combinations and new 

 genera, based on specific rather than generic characters. 



It is therefore to be hoped that Canadian botanists will 

 undertake the work of studying such plants of their own, which 

 need a revision, and, for instance, the ViolacecB would no doubt 

 prove to be interesting from a biological view-point, besides that 

 a close study of the various organs might reveal new characters 

 of importance to the distinction of several critical species. ^ Some 

 of these characters may be sought in the structure of both the 

 perfect and cleistogamic flowers, in the leaf-variation, the structure 

 of the rhizome and in the development of root-shoots. Having 

 studied the genus from time to time, the writer thought that the 

 publication of some observations upon the structure of these 

 organs might be of some interest to Canadian botanists, besides 

 that these notes might indicate the line of work to be pursu«d. 

 We might begin with 



THE FLOWERS. 



Two kinds ot flowers are known to occur in the genus Viola : 

 the perfect, which we know is to be found in all the species, 

 and the cleistogamic, which is far from uncommon, but which, 

 nevertheless, seems characteristic of certain species, or perhaps 

 better ot certain sections of the genus ; it is absent in Viola pedata 

 and tricolor for instance. The perfect flower is, as we 

 remember, hermaphrodite and zygomorphic, i.e., symmetry in one 

 plane ; the sepals are prolonged backwards beyond their point of 

 insertion, they are glabrous or hairy, often ciliate, and we have 

 noticed much variation in their shape and in the length of their 

 appendages ; the corolla is polypetalous with the anterior petal 

 larger and, sometimes, of a diff^erent outline from the others, 



1 The very work suggested by Dr. Holm is now being carried on at the 

 Central Experimental Farm by Dr. James Fletcher, who has under cultivation 

 there ill the Ottawa species and many from otheV parts of Canada. The 

 results of Dr. Fletcher's studies will doubtless be given to the Club when 

 they have been completed. — Editor. 



