THE FAMILIES OF FLOWERING PLANTS. 5 



tipped with a long, \i^]iip-like awn which eqiials or exceeds in length 

 the rest of the calyptra." 



The following localities are recorded with the date of collection: 

 Columbus, Ohio, W. S. Sullivant, 1841. Lancaster, Ohio, 1849-1850. 

 Distributed by Sullivant and Lesquereux in their Musci Boreali Anier- 

 icani as numbers 109 and 163 from " Lower Ohio and Southern Ken- 

 tucky" in 1856 and T865. Dells of the Wisconsin River, Wisconsin 

 E. G. Knight, fruiting, 1883. Ferns, Indiana, L. M. Underwood, 1891. 

 Wisconsin Dells, L. S. Cheney, fruiting, 1894. Lamoille Cave, Min- 

 nesota, J. M. Holzinger, 1894. 



THE FAMILIES OF FLOWERING PLANTS. 

 By Charles Louis Pollard. 



INTRODUCTION. 



THE first difficulty encountered by the average beginner in sys- 

 tematic botany lies in the recognition of those groups of plant 

 genera which we call families. Of a species or genus a rea- 

 sonably clear conception exists, even among those whose 

 knowledge of plants is very slight. Every farmer, for example, knows 

 that clover is a general or generic terin for the particular varieties 

 which he distinguishes as white, red, alsike, hop clover, and so on. 

 The various species of oaks or ashes, greatly as they may differ in 

 detail, are always recognizable as oaks or as ashes. But how much 

 stranger it seems when we are told that the clover and the pea or bean 

 belong to one and the same family ; or that the larkspur, with its odd 

 blue flowers of most irregular shape, is just as truly a member of the 

 buttercup family as the little yellow buttercup with its five equal 

 petals. The ability to determine a plant, either in the case of the 

 amateur or the trained botanist, depends entirely upon the degree of 

 acquaintance with family characteristics. There are many nearly 

 related families, and a knowledge of each of these will save many a 

 wrestle with a plant, for example, which seems to fit among the mints, 

 having flowers in whorls, tubular corolla and opposite leaves, but 

 which one cannot possibly find described among the labiatse in any 

 manual. It would have been so easy, with some knowledge of the 

 plant families, to remember that all the mints are distinguished by 

 their peculiar fruit, which is not capsular, like that of our specimen. 

 It then becomes a simple matter to refer the latter to the foxglove 

 family as a species of Pentstemon. In this connection it will be seen 

 how unreliable is the method by which color, for example, is made the 



