154 POI.VGOXUM ARIFOIJUM. 



IIALBERD-LEAVED TEAR-THUMB. 



in favor of dividing the genus. Thus Mr. Sereno Watson, in a 

 paper pubhshed in the "American NaturaHst," for 1873, says 

 that it ou<;-ht to be " restricted to the two sections Avicularia 

 and Tcp/iisT If this view should prevail, our present plant 

 would cease to be a Polygonum, and would have to be called 

 Tiniaria arifolia, since it belongs to the subsection Tiniaria. 

 A discussion of the technical points involved in these questions 

 is, however, entirely beyond the scope of these pages, and we 

 must therefore rest satisfied with having called the reader's 

 attention to the facts noted. 



The name Polygoimm is quite old, and is identical with the 

 Polygonum of Dioscorides. Pliny also mentions the plant, with 

 the remark that it is used to stanch blood. The species which 

 were known at the time of these Avriters, and which are still 

 included in the genus, are noted for their knotted and bent 

 stems, and this peculiarity suggested the name, which signifies 

 "many-kneed." Our plant scarcely does justice to the name, 

 however ; for, although it has a somewhat zigzag or bent habit 

 of growth, it is free from the knotty knees of some of the 

 related species. The specific designation, arifolium, refers to 

 the leaves, which resemble those of many of the species belong- 

 ing to the Arum Family. 



Polygoimm arifolmm always impressed us as having a delicate, 

 graceful beauty, well worthy of admiration, and probably most 

 persons who examine the accompanying plate will agree with us. 

 Botanists, however, generally regard it as nothing but a weed. 

 Dr. Darlington speaks of it as follows : " This and P. sagittatum 

 usually grow in company, clambering over other plants, and 

 forming entangled bushes. Both are worthless, unwelcome 

 weeds, in meadows, especially among second crop hay." So 

 sharp a criticism from so amiable a man as Dr. Darlington is 

 rather surprising; but the allusion to the "second crop hay" 

 makes it evident that, for the moment, he had forgotten he was 

 writing on general botany, and had fallen into a train of ideas 

 which would have been quite natural in his " Agricultural Bot- 



