200 AMERICAN MIDLAND NATURALIST 



recurved style. The style may be sectioned even with a razor 

 blade and the course of the pollen tubes traced within. Better 

 results can perhaps be obtained by embedding in parafin and 

 making thick sections of the style with any ordinary students 

 microtome. Any of the caulescent or acaulescent violets serve 

 the purpose. The flowers of Viola cucullata are, however, among 

 the most suitable because of their larger size. The violet is readily 

 distinguished even in summer by the long auricles to the rather 

 long unequal sepals of the cleistogamous erect or ascending flowers. 

 The flowers are in condition of showing pollen tubes when the 

 peduncle which is at first erect, begins to curve giving the ovary 

 a reflexed position. The degree of curvature is often a good indi- 

 cation of the various stages of fertilization. Viola cucullata is 

 usually formed in most situations, and bears a great abundance 

 of cleistogamous flowers until late in fall. 



POLYGONUM LONGISTYLUM SMALL, A SYNONYM. 



BY J. A. NIEUWLAND. 



On reading Rafinesque's description of his Polygonum bicorne^ 

 in the Flora Ludoviciana one can scarcely hesitate in believing 

 that this author, or Robin from whom he may have gotten an 

 original description, had in mind or more likely at hand, an ab- 

 normally large specimen of Polygonum longistylum Small. -^ There 

 are characters about the description especially that of the "elon- 

 gated exserted styles," that are unique for this plant, and found 

 in no other American Persicaria. The locality in both cases of 

 publication is the same. Rafinesque describes the plant as large, 

 four or five feet high; Small's plant is given as but one or two 

 feet high. If this discrepancy in size may be overlooked, then 

 Small's name is a synonym. As the work of Rafinesque is rare, 

 I shall quote the paragraph of his diagnosis in full: 



"75. Polygonum bicorne. Raf. Caulibus ramosis, ramis 

 geniculatis, patulis teretibus intus crenulatis; foliis petiolatis, 

 lanceolatis, glabris; floribus spicatis confertis octandris, distylis, 

 staminis inclusis, stylis exertis elongatis. Raf. — Renouee i, 



1 Rafinesque, C. S. Flora LiKloviciana, p. 29, (1817). 



2 vSmall, J. K. Bull. Torr. Hot. Club, i. p. 161), (iS()4). also, do. 

 Monograph Am. Sp. Polygonum p. 62, (1895). 



