THE AMERICAN MIDLAND NATURALIST 65 
Potentilla by virtue of the theory of residues, then we may say 
that Pentaphyllum was separated as validly as soon, if not sooner, 
leaving Potentilla -Anserina as the type even if we apply the very 
theory of residues to which appeal may be made to excuse the 
procedure referred to. Pentaphyllum was separated from the 
Linnaean Potentilla by Ludwig-Boehmer (1760), special reference 
being made to Potentilla reptans in its specific name. (‘‘ Potentilla 
foliis digitatis caule 1epente pedunculis unifloris, Linn. Sp. Pl. p. 
499 N. 17’’). In fact segregation of Pentaphyllum were made as 
early as 1754! Possibly the segregations may be looked upon as 
“hyponyms”’ perhaps because not published in connection with 
a binary name? Hill segregated the plant under the name Pen- 
taphyllum vulgare in 1756, twenty-two years before Lamarck’s 
date of Argentina. 
That it is very hard to find just by what principle of nomen- 
clature as to residues, types, priority and the like, the Ilustrated 
Flora (1913 ed) was written we may select the following examples. 
Bilderdyckia Dum (1827) certainly antedates Timiaria Webb. and 
Mog. (1836-40). ‘The author we feel confidant knows that the 
name Pentaphylloides is older than Dasiphora. It would scarcely 
do for the author to say that he rejects names ending in ozdes 
for he has such not a few. JBildedyckia is not a very beautiful 
name, but there are others in the Flora that are worse in more 
ways than one. Thelypteris is an older name than Dryopterts, 
but why not acceptable to the Illustrated Flora is a problem we 
can not hope to solve. Perhaps, Thelypteris was not published in 
connection with a binary name. Nor for that matter were Lin- 
naeus’ own genera Exythronium Hydiocharis etc. as elsewhere 
pointed out. 
That the author does not put much stock in the theory of 
residues would appear from the fact that the common Dandelion 
is kept under Leontodon contrary to all the precedent of a century 
or more, and in spite of the fact that Taxaxacum was first seg- 
regated from the Linnaean aggregate. An exactly parallel pro- 
cedure would result in the acceptation of Nymphaea alba Linn. 
for type of Nymphaea and the reduction of Castalia to synonymy 
although older than Nuphar. This would be the logical thing to 
do by every principle of analogy and reasoning. 
Historically there can be no question that the white water 
lilies are typical of the genus. Even Dioscorides himself brings 
