1908] Flora of the Boston District,— II 59 
REPORTS ON THE FLORA OF THE BOSTON 
DISTRICT —II. 
THE local flora committee of the New England Botanical Club 
has continued to collect information as outlined in its first publica- 
tion (RHODORA, ix. 81). Numerous botanists have contributed to 
the work by sending card-records regarding their specimens, and the 
collections of the Gray Herbarium, the Arnold Arboretum, and the 
New England Botanical Club have been personally examined. No 
doubtful records have in any case been included in the following 
list, and every species is represented by at least one herbarium speci- 
men. Any additions will be welcomed, for the present list is regarded 
as by no means final. 
There is need of much fuller information in regard to soil, moisture 
and other ecological factors, and future reports to the committee will 
be of greater value if they are more detailed than most of those we now 
have. 
There is a large block of towns south of the Blue Hills, which are 
very little known botanically. We have no reports from the South 
Shore, and Bridgewater, Easton, Canton and Norfolk are the only 
inland towns which are well represented among our records for this 
section. ‘The committee therefore urges upon the collectors of this 
district the importance of more detailed exploration south of the Blue 
Hills. The Committee will also try personally to collect in these 
towns as extensively as possible, but there is great need for coópera- 
tion in this part of the work. 
The Isoétaceae of this list have been contributed by Mr. А. A. 
Eaton of the Ames Botanical Laboratory. The committee wishes to 
thank Mr. Eaton for his zealous coóperation in this and other matters 
connected with the work. 
MARSILEACEAE. 
MARSILEA. 
M. QuaDRiIroLIA L. Introduced in muddy bottoms of lakes and 
streams; Charles and Concord Rivers; Glacialis and vicinity, 
Cambridge; Malden (1877, M orong); Boxford. 
