639 
celi is generai, and there are some in which marginai, intercalary, 
and apical growth are passed through in turn in thè sanie genus. 
Why then, one may ask, may \ve not expect intercalary and apical 
growth of thè thallus within thè limits of thè Florideae, a group 
which is of no higher generai organisation than thè Phaeophyceae? 
The agreement in thè colour of thè chromatophores of thè Ban- 
giaceae and Eu-Floridese 0 is regarded by Schmitz as of physiological 
signifìcance only and not worthy of much consideration in thè con- 
struction of a naturai System. The absence in thè Bangiaceae of thè 
well-known pits found between thè thallus-cells in thè Eu-Florideae 
is a striking anatomical difference but in thè light of our knowledge 
of thè generai existence (no doubt in thè Bangiacese as in thè rest 
of thè vegetable kingdom) of thè continuity of thè contents of adja- 
cent cells by fine strands of protoplasm passing through thè cell- 
walls one cannot attach much taxonomic value to this anatomical 
character. Pits very similar occur in some Phceophycece. 
2. Reproduction. — In both thè Eu-Florideae and thè Bangiaceae 
there are two modes of reproduction, asexually or vegetatively , by 
neutral spores (known in thè Eu-Florideae as tetraspores) and sex- 
ually, by carpospores which are thè more or less direct result of 
an act of fertilisation, thè male organ, thè spermatium, fertilising thè 
female organ, thè carpogonium. Let us compare these two kinds of 
reproduction in thè two groups. 
A. Vegetative. 
In thè Eu-Florideae neutral spores are known in most of thè gen- 
era and are usually formed by thè division of thè contents of thè 
mother-cell, thè tetrasporangium, into four cells, thè tetraspores, 
which escape into thè water and give rise on germination to new 
plants. Occasionally, i. e. in some individuai genera thè contents of thè 
tetrasporangium escape undivided as a monospore, or divide into two, 
bispores, or into many, polyspores. 
In thè Bangiaceae thè neutral spores are not definitely^ arranged. 
I propose in thè rest of this paper, to speak of thè Florideae, exclusive 
of thè Bangiaceae, as thè Eu-Floridem and include in thè Bangiaceae thè ge- 
nera Bangia, Porphyra, Wildemania, Erythrotrichia and Goniotrichum. 
One would not exclude a Palm from thè Palraeae because ito endosperm- 
cells did not shew thè usuai pts found in thè Palm seed endosperm. 
