170 Rhodora [SEPTEMBER 
mentioned in Dame & Collins’ Flora of Middlesex County, but with 
little data as to their relative abundance, and in some cases without 
much assurance that they were persisting at all. 
With a hope of placing on record the actual although to some ex- 
tent disappointing results of Mr. Pratt's work, and reducing the plants 
concerned to as definite a status as possible, we have applied for in- 
formation to Mr. Alfred W. Hosmer, whose long and close familiarity 
with the flora of Concord permits him to speak with much authority 
upon these plants. Mr. Hosmer has most kindly sent the following 
lists, the first showing twenty-four species which have persisted through 
the last twenty or more years, and the second indicating those species 
which are said to have been introduced by Mr. Pratt, but now thought 
to be entirely extinct in the region. Considering Mr. Hosmer's well- 
known and intensive exploration of the Concord flora, we have no 
hesitation in recommending that plants of the latter list be hereafter 
omitted from local floras of the region, since they have had only a brief 
and horticultural relation to the vegetation of Concord. 
PLANTS KNOWN TO HAVE BEEN INTRODUCED BY MINOT PRATT AND 
PERSISTING IN RECENT YEARS: 
ALFRED W. HOSMER. 
Hepatica acutiloba, DC., one station, spreading. 
Xanthorrhiza apiifolia, L'Her., one station in the Esterbrook 
woods, spreading. Mr. Pratt’s record says “ Plant found on Monu- 
ment street, 1870; propagated and set out on Mill brook.” 
Caulophyllum thalictroides, Michx., one station. 
Dicentra Cucullaria, DC., one station, but spreading. 
Viola rotundifolia, Michx., a few plants left. 
Claytonia Virginica, L., spreading somewhat. 
Oxalis Acetosella, L., spreading. 
Acer spicatum, Lam., growing finely. 
Potentilla tridentata, Ait., spreading somewhat. 
Tiarella cordifolia, L., two stations, spreading. 
Dodecatheon Meadia, L., one station. 
Sabbatia chloroides, Pursh, one station, barely holding its own. 
Two stations have disappeared within five years. 
Pogonatum giganteum, Dietrich, spreading. 
Cypripedium pubescens, Willd., three plants only. 
