148 The Ottawa Naturalist. [Feb. 



In this paper the authors will endeavour to give 

 a brief account of the general characteristics of violet hybrids 

 and also a list of the hybrids recorded from the North American 

 continent. 



ToTthe.Jamateur botanist who has neither time nor incli- 

 nation to study with earnest perseverance the multitude of 

 violets occurring in our woods and meadows, the existence of 

 intermediate forms between different species is at first apt to 

 provoke confusion and discouragement. A closer study of those 

 intermediate forms which at first may seem to blur the system- 

 atic boundaries between well defined extremes belonging evi- 

 dently to different specific units will, however, instead of causing 

 confusion, help most comprehensively to avoid it. In other 

 words, the recognition of certain intermediate forms as casual 

 hybrids will prove one of the most helpful means to the botanist 

 endeavouring to arrive at a well founded understanding of the 

 systematic value and relationship of our violets. 



The hybrid nature of puzzling forms, apparently interme- 

 diate between two species, can be most easily determined. 



The general appearance of hybrid plants, their vigorous 

 vegetative development, their bright and abundant flowers 

 and, generally speaking, their air of strength and splendour is 

 often very characteristic. When odd plants displaying these 

 marks are. found in violet colonies composed of two or more 

 species, they very often prove to be typical hybrids between 

 well defined species. 



The vegetative superiority of hybrids in plants is, however, 

 a too well known feature to warrant a lengthy discussion. It 

 is sufficient to say for the sake of illustration, that for instance 

 hybrids in the genus Epilolium and in grasses are always 

 characterized by their conspicuously vigorous vegetative organs. 

 Not only do they display a most luxuriant growth as far as foliage 

 and profusion of shoots are concerned, but their ability to survive 

 and hold the ground is far more pronounced than that of any of 

 their parents. Several observations have thus been recorded to 

 the effect, that hybrids between species of Epilobium, origi- 

 nating in a ditch or any other area of limited extension, are able 

 on account of the superior strength of their vegetative organs, 

 after a few years, to take possession of every inch of the ground, 

 killing every plant of the species from which they originated. 

 Similar observations have been made on violet hybrids. In 

 botanic gardens, where several species of violets are grown in 

 close proximity, it has been recorded that species, after a few 

 years, often have been killed and replaced by more vigorous 

 hybrid plants. 



