THE AMERICAN BOTANIST, 39 



quite a while. The foliage of the California baA' {UniheJl- 

 ularia California) reeks with the odor of hay rum and to 

 smell it for a few minutes will develope headache. Over in 

 the San Jacinto Canons we came across an asclepiad [Sar- 

 costemma heterophylla) which for vileness of smell beats 

 anything vegetal that m}' nostrils have so far en« 

 countered — a sort of sublimated essence of stale garlic and 

 onion, like the smell you generally encounter in the entry 

 of a third rate boarding house multiplied 133^ a hundred— 

 so we got into the way of calling it "the third-class board- 

 ing house plant." Sodocommon names arise. — C, F.Saun- 

 ders. [The probable explanation of the strong odors poss- 

 essed by plants in arid regions, is doubtless to be found in 

 the fact that certain oily secretions help them to resist evap- 

 oration. These oils would therefore be likely to abound 

 in plants of dry regions, and as most of them are strong 

 scented, the plants would naturally give off the same 

 odor. — Ed.] 



The Definition of a Weed. — I have been interested — 

 and somewhat preturbed (mildlj^) as to the definition of 

 a "weed" and I have struck upon three definitions. The 

 botanist's: A weed is a plant out of place. According to 

 this a rose plant would be a weed in a cornfield. The gar- 

 dener'' s : A weed is a plant which grows unbidden, and in- 

 sists on surviving under no matter what adverse condi- 

 tions. You may expose the roots or give other unfavor- 

 able conditions and it insists on living and doing what it 

 can to make it unpleasant for the plants 3'ou wish to 

 raise. The popular: A weed is a plant of spontaneous 

 growth. In some cases the three are in accord, in others 

 they are at variance. — E. W. 



