12S THE PLANT LIFE OF MARYLAND 



the Nanticoke it begins to occur just north of Vienna and becomes 

 abundant at the confluence of Marshyhope Creek, extending thence 

 up the river to Seaford, Delaware and beyond. The White Cedar, 

 unlike the Loblolly, occupies the lowest parts of the swamp and is 

 indeed most frequent along the very margin of the water. The 

 only plant which has been detected as a constant associate of the 

 Cedar and absent from other portions of the Stream Swamps is 

 Alnus maritime/,, a fall-flowering species of Alder which is prob- 

 ably endemic to the Chesapeake-Delaware peninsula. The common- 

 est of the secondary trees are the Black Gum, Magnolia, Sweet Gum 

 and Black Willow ; the Swamp Oak and the River Birch being pres- 

 ent in the swamps which border some of the smaller streams. The 

 commonest shrubs are Clethra alnifolia, Alnus rugosa, Cephalan- 

 thus occidentalis, Decodon verticillatus, Gornus amomum, Ha vir- 

 ginica, Rhus remix, Viburnum dentatum. 



These form a close stand together with some of the larger of the 

 herbaceous plants, the whole often forming thickets which are dif- 

 ficult to penetrate. The herbaceous plants are altogether more sun- 

 loving species than those found in the River Swamps. Among the 

 most characteristic may be mentioned : 



Rosa Carolina 

 Care.v prasina 

 Typha latifolia 

 Osmunda cinnamomea 

 Impatiens bi/I<>r<i 

 Saururus cernuus 

 Osmunda regalis 

 Sagilfarin latifolia 

 Cicuta maculata 

 Rume.r verticillatus 

 Peltandra virginica 

 Pontcderia cordata 

 Vernonia noveboracensis 

 Polygonum hydropiper 

 Iris versicolor 



