INTRODUCTION 25 



etc. Likewise our river and pond cypresses differ in their knees, 

 bark, leaves, power of resistance to fire, relation to seasonal fluc- 

 tuation of water, and especially in geographical distribution ; and 

 to call them all one species, (as some "authorities" who have gone 

 to extremes in splitting other genera have done until quite recently) 

 would be to shut our eyes to some very obvious and significant 

 facts. 



In this catalogue a rather conservative (and pragmatic) course 

 with regard to species and genera has been followed, for it seems 

 more desirable to spare the 'lay" reader mental exertion and at the 

 same time to keep the expense of printing, storage and mailing 

 within reasonable limits than to list as many species as possible 

 merely in order to make Alabama's list longer than that for some 

 other state. In some of our genera of woody plants the species 

 have lately been so finely divided by specialists that only an expert 

 can distinguish them, and then perhaps only by having leaves, 

 flowers and fruit taken from the same tree at different seasons. 

 (See remarks under Jnniperus, Crataegus and Tilia in the cata- 

 logue). 



NOMENCLATURE. 



Another question closely connected with classification, but not 

 quite the same, is nomenclature. Every plant that is known to 

 scientists has a scientific or technical name, which is usually Latin 

 in form if not in derivation. These are more or less objectionable 

 to the layman, but are necessary for the sake of definiteness. 

 Many plants are so small or rare or unimportant that persons other 

 than botanists have never had occasion to give them names (as is 

 true also of the vast majority of shells and insects) ; and what is 

 worse, quite a number of plants which are obviously and unmistak- 

 ably different go by the same common name in different parts of 

 the country or even in the same region, which would cause con- 

 fusion as if they did not have different scientific names. (The 

 same scientific name has indeed often been given to different 

 plants through oversight, but such mistakes are always rectified 

 as soon as possible.) For example, right here in Alabama we have 

 two short-leaf pines, two cypresses, several red oaks and water 

 oaks, three or four bays, two tytys, two black gums. etc. 



