24 METASPERMAE OF THE MINNESOTA VALLEY. 
the nutritive tissues indifferently termed endosperm, in which- 
ever way it is produced. 
The production of “seeds’’ Thisis considered by the writer 
as of less taxonomic importance than the other points which have 
been mentioned, especially as the ‘‘seeds” are such different 
structures in the Archispermae and Metaspermae, However, 
the older botanists considered seeds as structures of great 
importance and in consequence the plants which produce seeds 
have been grouped together under the name of Spermaphyta. 
Linnaeus recognised this division, but gave it the name Phaner- 
ogamia under a mistaken notion that there was an analogy 
between two such widely diverse phenomena as pollenisation 
and fertilisation. The confusion brought about by this mistake 
has lasted until our own day. Later it was proposed to call 
these plants Anthophyta, or ‘‘plants which produce flowers.” 
Those peculiar groupings of spore-bearing organs and acces- 
sory foliar structures which are termed flowers have, from their 
conspicuous character and high specialisation, always received 
particular attention and thus easily arose the early classifica- 
tion of vegetable organisms into flowering and flowerless 
plants—the Phanerogamia and Cryptogamia of Linneaus. These 
divisions were based, however, not upon fundamental morpho- 
logical characters but upon accessory, and have been pretty 
generally superseded by systems of classification which present 
a truer perspective by emphasising the more fundamental 
structural and developmental characters. 
The classification of Engler and Prantl. In the Natwertichen 
Phlanzenfamilien Engler and Prantl adopt a classification based 
upon characters of somewhat different value from those 
discussed above. They divide the vegetable kingdom into four 
branches:—I. Mycetozoa, slime-moulds; II. Thallophyta (in the 
widest sense); II]. Embryophyta zoidiogama (plants producing 
ciliated spermatozoids and building up sporophytic embryos); 
IV. Embryophyta siphonogama (plants producing pollen-tubes 
and building up sporophytic embryos). It will be seen that 
in this grouping a much greater merging of characters is 
permitted than in the one outlined above. In the first place, 
by way of individual criticism, the writer is inclined to suggest 
that the Mycetozoa are more properly classed with the animals. 
The presence of a contractile vesicle alone, need not determine 
animal rank among those organisms that Haeckel terms Protista; 
but its presence coupled with the absence of chlorophyll is 
strong argument. Volvox globator, with its coenobial growth, 
