20 Rhodora [FEBRUARY 
b. Lower sheaths rough-hispidulous with short stiff as- 
cending setae; perigynia ascending, moderately inflated, 
loosely investing the achene, chiefly ovoid.............. var. gynandra. 
a. Perigynia manifestly granular with numerous minute 
papillae, distinctly 2-4-nerved on both faces, the nerves 
reaching the apex or near it, lenticular, scarcely inflated, 
distinctly longer than the achene; achene broadly ovate 
to suborbicular, not at all bent or contorted; lowest sheaths 
CN TINIE MENDA C. Mitchelliana 
POLYGONUM DENSIFLORUM Meisn. Fl. Bras. v. pt. 1. 14 (1855). 
P. portoricense Bert. ex Small, Monog. Polyg. 46, t. 10 (1895). P. 
eciliatum Stone, Pl. Southern N. J. 423 (1910), as to plant, but not 
as to name-bringing synonym. Persicaria portoricensis Small, Fl. 
Southeastern U. S. 377 (1903). 
There appears to be no nomenclatorial bar, under any code, to 
the use of the name Polygonum densiflorum Meisn. P. densiflorum Bl. 
of the Index Kewensis is an error. What Blume published in the 
passage cited, Bijdr. 533 (1825), is P. corymbosum e densiflorum, 
a varietal, not a specific name. Blume’s variety is generally referred 
to P. chinense L. as a synonym: I do not find that anyone had raised 
it to specific rank until this was done through inadvertence by the 
editors of the Index, long after Meisner had applied the same com- 
bination to a wholly different plant. 
Meisner’s name seems also correctly applied to the plant of the 
southeastern United States and the West Indies. In his original 
treatment in the Flora Brasiliensis, Meisner included in P. densi- 
florum a Brazilian plant with somewhat ciliate sheaths and eciliate 
specimens from Louisiana, the West Indies, Peru and Chile. He 
specified no type. Later, in the Prodromus xiv. 121 (1864), he divided 
the species, as thus constituted, into two varieties, g imberbe, includ- 
ing the plants of the United States, the West Indies and western 
South America, and 8 ciliatum, based on the Brazilian plant, of which 
he seems to have had only one collection. Since Meisner placed our 
plant in var. g and since in his time a variety so designated was held 
to be typical of its species when any such distinction was made, it 
may reasonably be considered that Meisner himself indicated the 
plant of the United States and the West Indies as typical of P. 
densiflorum. The Chilean and Peruvian plants, of which I have seen 
no specimens, might not now be regarded as conspecific with ours; in 
view, however, of the wide ranges of other hydrophilous species of 
the section Persicaria, such as P. acre, itis by no means a necessary as- 
sumption that they are not, 
