Harshberger : Plant formations of Nockamixon Rocks 661 



gea arborescens^ Rhododendron maxhmcm (in thickets), Vibiirnum 

 acerifolunn^ and the Virginia creeper, Ampelopsis qninquefolia. 



Shade herbs : The herbs that grow in the dense shade are 

 Pilea ptimila, Laportea canadensis^ Hepatica triloba^ Thalietnvi pur- 

 pur ascens {T, reiwhitnni)^ Mitella diphylla, Snnlacina racemosa, 

 Maiantheniiiui canadeuse, hnpatiens f2iha{I. biJlora\ m\6.Adiantum 

 pedatian^ which occupies the outcropping rock masses. As this 

 ravine is ascended, the woods become drier and the hill slopes 

 more gradual and the ravine vegetation fuses with that of the crest. 

 The valley back of the Narrowsville Hotel is characterized by 

 a stream the flat banks of which show the presence of Juglans 

 cinerea^ Fraxiniis americana^ Carpinus caroliniana, Betida lenta, 

 Tilia a)nericana^ Liriodendron Tulipifera (sparingly), and such 

 shrubs as Auielanchier canadensis, Lindera Benzoin {BenBoin aesti- 

 vale)^ Hydrangea arborescens^ and Rtibus oceidentalis. On the 

 slopes above a small waterfall are assembled Dry opt e7is marginalise 

 PolysticJiiun acrosticJioides^ Asarum canadense^ Aquilegia canadensis, 



4 



Impatiens fulva (/. bijiord), while on the steep rocks overhanging 

 the stream are found the walking fern, Camptosorus rhizophylhis 

 and the columbine, Aqtnlegia canadensis. 



In the bottom of another ravine, the forest consists of such 

 trees as Acer Saccharum, Fagtis americana {F, grandifolia), Quer- 

 ens coccinca^ and, sparingly, Liriodendron Tulipifera. The shrubs 

 are Hanianielis virginiana, Corylns americana^ Hydrangea arbor- 

 escens^ Rnbns odoratns, Lindera Benzoin {Benzoin aestivalis^, Sam- 

 bucus racemosa^ and Vibnrnnm acerifolium, Tlie yew, Taxns cana- 

 densis^ forms extensive masses, as elsewhere on the cliffs, while the 

 marginal shield fern occurs in extensive patches. The forest floor 

 is occupied by a covering of quite a ^^^ characteristic herbaceous 

 plants, such as Sanguinaria canadensis, Snnlacina racemosa, Ari- 

 saenia triphyllum, Asarum virginicuni, Adiantum pedatum, Botry- 

 chium virginianunty and on the rocks dripping with water occur the 

 moss Eurynchium Mans and the liverwort Marchantia polymorpha. 

 Lower down, where the stream breaks over a rock face about 1 5 feet 

 high, the ravine narrows and the hemlock, Tsuga canadensis, be- 

 comes more abundant, associated with Betula IcJita and Acer Sac- 

 charnm to form a facies (the maple-birch-hemlock facies), including 

 Qnei'cus rubra, Rhododendron maximum, Corylus americana, ILy- 



