THE AMERICAN BOTANIST 49 



of grazing animals but whether these are their principal uses 

 we cannot be sure. Recently botanists have been asserting 

 that the epidermal hairs of many plants are useful in obtain- 

 ing free nitrogen from the aii. Up to very recent times we 

 have been taught that practically all the nitrogen iu plants is 

 taken from the soil in the form of nitrates but the investiga- 

 tions of several Old World botanists put a new face on the 

 n'latter. It has been known for some time that forest soils 

 steadily gain in nitrogen content from the decay of the leaves 

 of trees which seems to give additional evidence in favor of 

 the new theory, but further investigations must be made before 

 the idea is likely to be accepted by botanists. 



Forms of Kalmia. — When one begins the intensive 

 stu'dy of any species of plant there seems to be no limit to the 

 number of forms that may be discovered. These forms are of 

 interest to the breeder and the student of evolution and if not 

 seized upon by the species-maker to further complicate the 

 nomenclature of the subject, are worth taking into account. 

 Practically any species of plant may be shown to have these 

 forms; even the nearly inflexible calico bush (Kalmia latifolia) 

 has several that bear latin names. Polypfala has partly double 

 flowers, alba has white flowers, rubra has deep pink flowers, 

 fuscata has flowers with a broad brownish purple band inside, 

 Myrtifolia has small leaves and forms a dense and compact 

 bush, and obtiisata has obtuse leaves. These, of course are 

 mere variations from the normal and even their describers had 

 no idea that they are distinct or permanent forms. Anyone 

 who chooses may describe a similar set of forms of other 

 plants. So long as all our plants are not thus divided the 

 study of botany, wil not be greatly hampered by the added 

 names and a few species-makers may derive enjoyment from 

 the results. 



