94 MISSOURI BOTANICAL GARDEN. 



writers on American botany. Wet sand along the sea- 

 coast of the northern Atlantic States, about salt springs at 

 various points in the interior, and on river banks, beaches, 

 etc., across British America, extending south ward to Illinois, 

 southern Calif ornia and Mexico. Specimens examined from 

 various points in British America, and from Massachusetts, 

 Rhode Island, New Jersey, Wisconsin, Illinois, Iowa, 

 Nebraska, Dakota, Montana, Idaho, Yellowstone Park, 

 Colorado, New Mexico, Nevada, California, Oregon and 

 Washington. Plate 32. 



The usual form, with narrow collosities and much 

 elongated bristles, differs from the European R. maritimus 

 only in the frequent wavy margin and obtuse base of the 

 leaves and the occasional development of a third bristle on 

 each side of the valves ; and a few sea-shore specimens 

 apparently belong to the normal form of the latter. If it 

 is kept apart from the European plant, it must bear the 

 name here employed, and I am inclined to think that it is 

 as distinct as most Old World species of the maritimus 

 group. But in any event, if precedence on a given page is 

 held to establish the priority of one name over another, 

 persicarioides has precedence over maritimus. 



R. crispatulus, Michx., Fl. i. (1803), 217, is the form 

 with broadest most wavy leaves, more naked inflorescence, 

 and larger valves, only two of them bearing unequal 

 callosities ; but a study of the many forms growing inter- 

 mingled about St. Louis, has not shown the wisdom of 

 maintaining it even as a variety. 



A specimen from Washington (Suksdorf, 1889, 943), 

 has nearly entire valves, but the usual form occurs under 

 the same number ; and a very similar plant is R. salicifolius, 

 var. (?) of Watson, Bot. King. 314, from Nevada ( Wat- 

 son, 1868, 1052). 



R. BUCEPHALOPHORUS, L. Annual, a span or two high, 

 spreading, slender, simple or with few subequal branches, 

 glabrous and apparently somewhat glaucous ; leaves scarcely 



