THE AMERICAN BOTANIST 101 



Spanish Peas. — What are Spanish peas? Among other 

 things that the Government has forbidden to be exported to 

 Mexico are Spanish peas, but no indication is given of their 

 botanical affinities. Doubtless those down on the border know 

 all about them, but Bailey's "Cyclopedia of Horticulture" is 

 not acquainted with them — at least under the name given — 

 and we have not been able to find anybody else who is. Can 

 any of our readers supply the information ? Specimens in our 

 possession do not closely resemble other peas. They are 

 used for human food in some parts of our country but no seed 

 catalogue, to which we have access, offers seeds. 



Soil and Plant Habitat. — The botanist and the flower- 

 gatherer soon come to recognize instinctively various plant 

 habitats, partly from the mere looks of the place and partly 

 from the conspicuous plants which grow there. So well 

 known is this connection between the soil and the plants which 

 inhabit it that we naturally expect to find certain species where 

 we find other very different ones growing. Fern hunters in 

 search of the adder's-tongue or the curly grass (Schicaca) 

 often rely upon "call plants" growing with them to indicate 

 their whereabouts. We do not expect hickory-nuts on every 

 wooded hillside, nor strawberries in every field. It all depends 

 upon the soil. This is also the reason we seldom find huckle- 

 berries, arbutus, laurel and the pink lady's slipper growing 

 with trillium, bloodroot, phloxes, mandrake, and the like. 

 Even the trees in whose shade these two groups of plants grow 

 are different. With the first group we find pines and oaks 

 and with the second basswood, ash, and maple. We find, how- 

 ever, that the soil not only influences the character of the plants 

 which grow in it, but the plants in turn influence the soil. The 

 leaves of certain plants produce acids when they decay while 

 others become alkaline. If the soil is calcareous, the acids may 

 be neutralized and form habitats in which our ordinary plants 

 can grow, but if the soil is acid only certain specialized plants 



