DESCRIPTION OP JACKSON COUNTY ix 



introduced species above mentioned abound in waste places. Chief 

 among these are : Panicum capillare, Panieum proliferum, Juncus tenuis, 

 Urtica gracilis, Polygonum aviculare, Polygonum Pennaylvanicum, Phyto- 

 lacca decandra, Portulaca neglecta, Lepidium apetalum, Lepidium Virginicum 

 (possibly introduced), Erxplwrbia maculata, Euphorbia nutans, Asclepias 

 Syriaca, Verbena strieta, Teuerium Oanadense, Solanum Carolinense, Vero- 

 nica peregrina, Plantago Bugellii, Plantago aristata, Vernonia interior, 

 Erigeron annuus, Erigeron ramosus, Leptilon Canadense, Iva dliata (lo- 

 cally), Ambrosia artemisiaefolia, Ambrosia trifida, Oarduus altissimus and 

 Laciuca Canadensis. 



Along the railroads many species are found, of some perhaps only a 

 plant or two, which hardly deserve a place in our flora, but whose occur- 

 rence it is necessary to mention in order to make a complete record. The 

 railroads at Sheffield are especially rich in such species. A few show a 

 tendency to persist and spread, but most of them are purely waifs. Quite 

 a number of such species are here reported, especially among the Grami- 

 neae and Compositae. 



At the end of the work will be found a table showing the number of 

 families, genera, species and varieties, from which a knowledge of the 

 component parts of our flora can be obtained almost at a glance. Our 

 largest genera with the number of species aud varieties in each are : Carex, 

 60 ; Polygonum, 20 ; Panicum, 17 ; Aster, 16 ; Cyperus, 13 ; Chenopodium, 

 12; Meibomia, 12 ; Solidago, 12 ; Quercus, 11 ; Euphorbia, 11 ; Physalis, 

 10 ; Helianthus, 10. Probably the most noticeable features of our flora 

 are the great number of grasses, Compositae and sedges, the total absence 

 of heaths and the small number of ferns and orchids. 



