85 
ALGiE. 
On the Necessity for Removing Ectocarpus secundus, Kutz., 
to a New Genus. 
By E. A. Batters, B.A., LL.B., F.L.S. 
In the genus Ectocarpus the ciliated zoospores are produced in 
well-defined sporangia, some of which are multilocular, while others 
are unilocular ; only the spores produced in the multilocular 
sporangia, however, have been observed to conjugate, those pro- 
duced in the unilocular sporangia being, in all probability, asexual. 
In Ectocarpus siticulosus (the typical species of the genus) the 
planogametes are, according to Berthold, at first similar in 
every respect ; some of them, however, soon withdraw their 
cilia and come to rest, while others remain actively motile. 
One of the still actively motile gametes then coalesces with 
one that has come to rest to form the zygospore ; should the 
gametes fail to conjugate, however, they are still capable of 
germinating independently. Dr. Bornet has shown, quite 
recently, that in certain species, e.g.. Ect. secundus , Kiitz., 
which have up to the present been ranked in the genus 
Ectocarpus , there is a much more marked differentiation of the 
sexual cells, the male and female cells being developed in distinct 
sporangia — antheridia and ogonia. The male cells, which are 
much smaller than the female, are produced in sporangia 
of a clear orange colour, while the larger female cells are borne 
in deeply coloured multicellular sporangia similar to the ordinary 
plurilocular sporangia of the typical species of Ectocarpi. No 
asexual sporangia have been observed on the species bearing 
antheridia, and Dr. Bornet conjectures that the latter are the 
homologues of the unilocular sporangia of the typical forms. The 
antherozoids are colourless and similar in all respects to those of 
Cutleria or Fucus. Taking the facts above stated into considera- 
tion it seems to me inadmissible to retain in the same genus 
plants like Ectocarpus siticulosus , Lyngb., in which, as has been 
seen, the reproductive process is isogamous, the male and female 
cells as well as the sporangia in which they are produced being 
similar in every respect — and Ectocarpus secundus, Kiitz. — in 
which the male cells and the sporangia in which they are produced 
differ in several important particulars from the female cells and 
their sporangia. I propose, therefore, to remove Ect. secundus , 
Kiitz. and its allies to a new genus, which, in memory of the late 
Miss I. Gifford, of Minehead, I have called Giffordia. The new 
genus will be characterized as follows : — 
