1907] Reynolds,— Flora of the Great Swamp of Rhode Island 117 
extreme form in which the two lateral lobes are reduced to large 
teeth, so that the leaves appear undivided and only coarsely dentate 
and are then ovate to ovate-oblong in shape. To this form belong 
the following two specimens: FLortpa, Chapman (herb. Gray) and 
Mississippi, Enterprise May 6, 1880 (herb. Arnold Arboretum). 
Considering the sporadic distribution of the variety tridens through 
the range of the species and the inconstancy of its characters as is 
clearly shown by a large number of specimens, one cannot consent 
to its elevation to specific rank, as was done by Pax, who in his earlier 
monograph distinguished even two species, A. microphyllum with 
smaller leaves very glaucous beneath and with the petiole shorter 
than the limb and A. semiorbiculatum with larger leaves, green (!) 
beneath and with the petiole longer than the limb, each species based 
apparently on a single specimen, collected by Kinn in “Am. bor." 
without indication of the locality. In his later monograph he reduces 
the latter species to a form of A. rubrum*and substitutes for A. micro- 
phyllum the name A. tomentosum. 
ARNOLD ARBORETUM. 
THE FLORA OF THE GREAT SWAMP OF RHODE 
ISLAND. 
ERNEST SHAW REYNOLDS. 
Tue Great Swamp of Rhode Island is a region which has long been 
recognized by botanists as offering a very rich collecting ground, and 
has often been visited by students of botany. The swamp is located 
in the southern part of the state, in Washington County, close to the 
junction of the town lines of Charlestown, Richmond, and South 
Kingstown. The larger part lies in South Kingstown, though a part of 
the western half is in the adjoining town of Richmond. It is entirely 
enclosed between the parallels 41° 25’ and 41° 30’ while the meridian 
71? 35' cuts the swamp area into two nearly equal portions. Excluding 
the part south of Worden's Pond, the swamp area covers about six 
square miles, which is the largest tract of land in Rhode Island bearing 
a swamp flora. 
