326 Annals of the Carnegie Museum. 



Toxicodendron pubescens, Vitis vulpina, 



Rubus allegheniensis Celastrus scandeiis, 



Diervilla Diervilla. 



The Herbaceous Layer. — The fourth layer consists of herbaceous 

 plants of various species, which usually alternate to some extent with 

 the layer next above, forming where not too much shaded a more or 

 less dense carpet of vegetation. The species are as follows : 



Corallorhiza viaculata, Chimaphila maculata, 



Aralia nudicaiilis, Galium circcBzans, 



Vagnera stellata, Hieracium scabrum, 



Vagnera racemosa, Hie7-aciiim Gronovii, 



Utii/oliuin canadense, Solidago ccssia, 



Meihoinia Dillenii, He/ianthus sfrumosus, 



Lespedeza capitata, lussilago Farfara, 

 Osmorhiza Claytoni. 



A few of the species in the herbaceous layer are of sufficient abun- 

 dance to dominate during certain aspects. The Aralia nudicau/is 

 society, the Vagnera stellata society, the Utiifolium canadense society, 

 and the Osmorhiza Claytoni society are especially to be noticed in 

 this connection. Each of them forms over certain areas practically 

 pure groups of'one species alone. A comparatively large proportion 

 of the species of the herbaceous layer depend more or less upon 

 creeping stems or rhizomes for their dissemination, this method being 

 especially favored by reason of the loose soil, in which the plant-food 

 is largely in the upper layers. The result of this method of dis- 

 semination is, of course, a more definite alternation of different species 

 into groups having the rank of family, conmiunity, or society. 



The Ground Layer. — The ground layer is very poor as to lichens 

 and mosses, but of the fungi, especially the Agaricaceae, there were at 

 times a considerable number to be seen. On account of inadequate 

 facilities for drying the specimens during rainy weather many of the 

 collections were lost, but the following were among the more abun- 

 dant species in the habitat : 



Russula virescens, Amanitopsis vaginata, 



Russula emetica, Armillaria niellea, 



Lactarius piperatus, Lentinus lepidtis, 



Amanita verna, Lycoperdon gemmatutn, 



