OUR AMPHIBIOUS PERSICARIAS 203 
perhaps, will not meet with favor among manual makers whose 
patterns of description are hide-bound, and whose volumes are 
made to cover an impossible area of the country, and rather to 
reimburse financially than to.give adequate information. There 
will undoubtedly come a time when students will reason that 
a little accurate knowledge is worth more than volumes of super- 
ficiality, when local floras will be more in demand than territorial 
ones; but for the present, what with the ignorance of the student 
and the prejudices or even ignorance of manual makers, descrip- 
tions under several captions of many polymorphic plants will 
continue to be a decided financial disadvantage, and so a more 
or less complete knowledge of the amphibious smartweeds will 
continue to be the heritage of a few. It has in fact come to such 
a pass that even otherwise reputable botanists label for the 
herbaria anything as P. amphibium L,. that has floating glabrous 
foliage. Any Persicaria that has spreading borders to its ochrea 
is called P. Hartwrightu, and any plant that has neither of the 
above characters is necessarily P. emersum! And for that matter 
these are about all the characters worth mentioning that the 
average manual considers. sufficiently distinctive. This fact is 
accounted for, because the average student of taxonomy does 
not for too long a time consider that there is anything worth 
knowing about plants not in a manual. We can not put any 
reliance on names of amphibious smartweeds labelled even by 
renowned botanists, because the plants being collected in one 
phase only, are at most but fragmentary, and the manual- 
gleamed information that impels the labelling, is still more so. 
-When therefore, as occasionally happens, a collector stumbles 
on a riparian specimen with both terrestrial and aquatic foliage 
on one shoot, in other words, contains all the above mentioned 
different and supposedly distinctive characters of the three species 
referred to, then arises the dilemma as to whether the plant is 
to be called P. amphibium, P. emersum or P. Hartwrightii. No 
matter how ignorant the student or unsophisticated in things 
botanical he .has usually enough common sense to know that 
two species could not grow in the same shoot no matter how 
different in appearance, and usually, unless he leaves his specimens 
unnamed and unlabelled, comes to one of two conclusions; either 
the manual makers are sometimes possessed of but average ig- 
