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quently this summary must be considered as, to a certain degree, 

 provisional, which a broader knowledge of the species may modify. 

 I have been compelled reluctantly to differ from Dr. Flngelmann 

 as to the relations and proper names of some of the forms. It 

 does not seem to me possible to include S. androcladitm under 

 5. simplex as a variety, although they are undoubtedly closely 

 allied. Not only does the former reach stouter proportions, but 

 Its inflorescence is branching, and sometimes almost as widely 

 branching as that S, eurycarpum, and its fruit is larger and 

 coarser. Besides this, S. androcladum is more aquatic in its 

 habits than the other. I was fortunate enough during the last 



summer to light upon a very interesting proof of the relationship 

 existing between this form and the deep water plant known as S. 

 simplex^ var, fluitans, Engelnu On the edges of a pond in the 

 neighborhood of my home, and in several widely separated local- 

 ities, vS. aitdrocladiim grew in abundance. From the banks the 

 plants ran down into the water until they reached a depth of four 

 or five feet, the leaves gradually increasing in length and thinness 

 and finally becoming floating, while the stems became more and 

 more slender, and the inflorescence, which ceased at a depth of 

 two or three feet, manifested a decided approach to the ''fluitans'^ 

 condition. This was not a case of submergence by flood, as the 

 water was lower than usual by several feet, showing that the 

 plants sought the water spontaneously. One step further and 

 the plant becomes so much altered as to appear quite distinct 

 from the parental form, warranting us in distinguishing it as a 

 variety. 



Nor am I able to agree with Dn Englemann in regarding the 

 distance of the floral leaves from the pistillate heads, or the 

 proportionate length of the styles and stigmas as affording good 

 varietal distinctions, these variations being very common and 

 very inconstant. Judging by them alone, I have been continually 

 perplexed to decide what is 5. simplex type, and what 

 "v. Nuttallii," what '' \. fluitans" and what "v. angnstifolium:' 



In separating the species, the simple or branching inflorescence 

 n^ight at first view seem to sufficiently designate the larger groups, 

 but such a grouping is unnatural as it associates species which in 

 reality are quite dissimilar. A more natural character is found 



