372 BICKNELL: FERNS AND FLOWERING PLANTS OF NANTUCKET 
Note.—The Labrador or jack pine (Pinus Banksiana Lamb.), 
which has been planted at Wauwinet, has been mistakenly at- 
tributed to Nantucket as a native tree (see Rhodora 18: 241-242. 
1916). 
*SAGITTARIA RIGIDA Pursh. 
Collected in Polpis, August 20, 1899, in flower and fruit, by 
Mrs. Nellie F. Flynn, who has kindly sent me a specimen from her 
herbarium for examination. 
/ 
*ECHINOCHLOA MURICATA (Michx.) Fernald. 
This well-defined segregate from LE. crusgalli, recently re- 
stored to recognition by Professor Fernald (Rhodora 17: 105-107, 
1915), belongs to the flora of Nantucket although its exact status 
there remains to be determined. I have collected it near the town, 
and have seen a specimen in Miss Gardner’s herbarium. It is 
locally common on Martha’s Vineyard. 
PANICUM VIRGATUM L. 
A well-marked smaller form of this species, described in Part 
II of this paper (Bull. Torrey Club 35: 184. 1908), answers per- 
fectly to the description of Panicum virgatum cubense Griseb. in 
Hitchcock & Chase, North American Species of Panicum (Contr. 
U.S. Nat. Herb. 15: 92. 1910). This form seems not to have 
been reported from east of Connecticut. 
*PANICUM TSUGETORUM Nash. 
Common in exposed sandy places and among open growths of 
oak and pine. The Nantucket plant is not the typical form 
described by Nash, but the stiffer and stouter more pubescent 
plant defined by Hitchcock & Chase. On Nantucket it is much 
more common than P. columbianum. Examples of each in which 
their differences are well expressed appear like perfectly sepa- 
rable species, but perplexing intermediates are so frequent that 
a broad treatment could scarcely present them as being unequiv- 
ocally distinct. Occasional densely tufted very pubescent forms 
with smaller closely flowered panicles of more numerous and 
smaller spikelets suggest hybridization with P. oricola. Slender 
and narrow-leaved forms with small panicles and spikelets seem 
to be quite intermediate with P. meridionale Ashe. 
