276 THE JOURNAL OF BOTANY 
The autumnal tubers are edible. 
In the account of the plant given in the Botanical Magazine 
accompanying the plate quoted above, it was stated that ee 
a) B 
tattor died in Canada in 1805. James Donn gave the year 1798 
for the — of introduction of his —— a which is 
also Canadian, and is now considered the same speci 
recent years recor is no record of the e species establishing itself 
within the limits of our flora, nor even of its cas 
in France in soft mud a eep ditches, by the banks of the 
Garonne and Riadciena footy in the neighbourhood of Bordeaux, 
where, however, only the male plants have been observed. 
Among recent authors it is agreed that Pursh’s two species, 
7 
un 
them was Dr. George ee who has made a life-long study 
of the family Alismatacee; he united them in 1856, as above 
quoted, and he adopted ae ve these two names for the 
co —— on. Micheli, is ph, followed t 
course in 1881, as also aid Garces in gn Catalogue of Conair 
Plaats; in ; 
On the other hand, Jared G. Smith in his work quoted above, 
and Buchenau, also Britton & Brown, have all preferred to use 
S. rigida Pursh for the name of the united species; but these 
cases are subsequent to 
ccording to the International Rules for botanical nomencla- 
ture, adopted at Vienna in 1905, the correct name for use under 
the circumstances is S. heterophylla Pursh; this decision is 
governed by Article 46 of the Code, which is as follows :— When 
two or more groups of the same nature are united, the name of 
the oldest is en see If the names are of the same date, the 
= es chooses, and his choice cannot be modified by subsequent 
aut 
There are two other wasnt ‘iho have also received the name 
8. Aecaeophayiia, one of them being older than that of Pursh, but 
neither of them now stands; rast are S. heterophylla Schreb. in 
