94 Annals of the Carnegie Museum. 



t R. verticillatus Linnaeus. Swamp dock. 



* R. crispus Linnaeus. Curled dock. 



* R. obtusifolius Linnaeus. Bitter dock. 



f R. conglomeratus Murray. Smaller green dock, 

 t R. sanguineus Linnaeus. Red veined dock. 



POLYGONUM Linnsus. 

 ? P. maritimum Linnaeus. Seaside knotweed. 



* P. aviculare Linnaeus. Door-weed. 



* P. erectum Linnaeus. Erect knotweed. 



* P. ramosissimum Michaux. Bushy knotweed. 



Allegheny R. R. near outer depot, 1886, Dr. A. Ziegler. 



f P. incarnatum Elliott. Slender pink persicaria. 



* P. Pennsylvanicum Linnaeus. Pennsylvania persicaria. 



* P. orientale l>innaeus. Prince's feather. 



* P. Persicaria Linnaeus. Lady's thumb. 



* P. hydropiperoides Michaux. Mild waterpepper. 

 =>= P. Hydropiper Linnaeus. Smart-weed. 



* P. punctatum Elliott. Water smart-weed. 

 P. acre Humboldt, Bonpland i\r Kunth. 



