EDITORIAL 



When it comes to distinguishing between closely 

 related forms or even species, the disposition of the 

 case is likely to be largely a personal matter. As has 

 been noted in this magazine, there was once a time 

 when the obtusilobata form of the sensitive fern was 

 regarded as a good species, though we now know it 

 to be a mere ecological form and worthy of a name 

 merely because it can be handled more expeditously in 

 literature if possessing such a handle. These obser- 

 vations come to mind in reference to Dr. Hill's re- 

 marks concerning the plant which we are inclined to 

 call Lycopodium lucidulum porophylum. In the letter 

 that resulted in our asking Dr. Hill to write down his 

 observations regarding the plant, he expressed the 

 opinion that this is a species distinct from L. luci- 

 dulum. Yet the very characteristics that lead Dr. 

 Hill to think this a distinct species are the ones that 

 incline us to regard it as a mere form. The surround- 

 ings of any plant have much to do with its form. 

 Plants accustomed to strong sunlight grow slenderer, 

 and with broader leaves when in shade. Similarly 

 when the so-called shade plants, such as the ferns are 

 exposed to strong light or considerable drouth this is 

 at once reflected in their forms. They quickly become 

 shorter, thicker, yellower, more fruitful and with 

 smaller leaves and fewer serrations. This is exactly 

 what we would expect if the shade and moisture lov- 

 ing lucidulum should find itself exposed to consider- 

 able drouth by reason of growing on a sandstone sub- 

 stratum. Whether this condition has existed for so 

 long that the two forms are now specifically different 

 and cannot readily be transposed is a matter about 

 which we can only guess, at present. What is badly 



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