16 
foreign plants unknown in any other town of the county, 
and perhaps not elsewhere established. 
Two or three plants observed along the shore of the 
Merrimac river suggest a close connection with the mills 
at Lowell and Lawrence, one of them being a southern 
sedge. Many plants are emigrating eastward from our 
western states, travelling as it were by rail. The Rud- 
beckia hirta, now quite common in fields hereabouts, ac- 
cording to Dr. Pickering, did not reach Philadelphia 
until 1826, and this vicinity until perhaps 1855. 
The latest arrival noticed (1878) is that of Eleusine 
Indica, a weedy, oriental grass which is common at New 
York city and Philadelphia. It has made its appearance 
"along the railroad tracks at the Pennsylvania. Pier, 
Salem, having travelled thence by the P. and R. R. 
R. Co’s steamers, which regularly bring coal from Phila- — 
delphia. This last comes under the head of “ballast 
plants,” a very full account of which may be found in the 
Torrey Bulletin for November, 1879. 
