70 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
assimilation consist in the former genus of starch, in the latter genus of 
some other substance, possibly the drops of mucilage. In Microspora 
there are two kinds of spores ; the megaspores have two or four cilia, and 
escape by the breaking of the wall of the mother-cell or by its gelatiniza- 
tion, and pass over, on germination, into a resting condition, either in 
the form of aplanospores or akinetes ; in Conferva megazoospores only 
are known, which are uniciliated, escape only by the rupture of the 
cell-wall, and germinate directly into new filament. The genera agree 
in having only a single nucleus in each cell, and in the structure of the 
cell-wall. 
Under Microspora, Lagerheim enumerates thirteen species, including 
two new ones, ilf. Willeana and ilf. 3Ioehii ; and in it are comprised also 
several species usually placed under Conferva or Ulothrix, as C. stag- 
norum, U. tenerrima, and JJ. seriata. Under Conferva, in which the 
resting-cells (not formed from zoospores) always have the form of 
aplanospores, two species only are named, C. hombycina and C. utriculosa. 
The author regards both these genera as fully formed organisms, and not 
as stages of development of higher alg£e. 
The other genera of the order are Hormiscia, TJrospora, Chsetomorplia, 
Ulothrix, Schizogonium, Hormidium, Bhizoclonium, Gloeotila, Binuclearia, 
and Uronema. Trihonema is a synonym of Conferva hombycina. 
Cephaleuros.* — This genus, found growing on leaves in Surinam’ 
and placed by its discoverer, Kunze, among the Mucoroidese, and later 
among Lichens, is now referred by M. P. Hariot to the Trentepoh- 
liacefe among Algse ; and he thinks it probable that it is the algal 
constituent of tbe lichen-genus Strigula, at least of some of its species, 
while those of other species of Strigula belong to the genera Phycopeltis 
and Protococcus, while other species referred to Strigula are not lichens 
at all. 
With regard to Hansgirgia flabelligera and Pliyllactidium tropicum, 
the author agrees with De Toni, I that these are distinct species, although 
the genera Hansgirgia De Toni, My coidea Hans., and Phyllactidium 
Moeb. should be sunk in Phycopeltis ; and the original 3Iy coidea of 
Gunn, is superseded by Cephaleuros. 
Botrydiopsis.f — Under the name Botrydiopsis arhiza Prof. A. Borzi 
describes a new species and genus of green algae belonging to the Botry- 
diaceae. It occurs in the form of a dense green layer on a wall over 
which water is constantly trickling. In its ordinary condition it con- 
sists of perfectly spherical cells, in some cases as much as 30-40 /x in 
diameter. It possesses a distinct but very thin membrane clothed with a 
number of chromatophores. In young individuals the protoplasm is 
homogeneous, with a nucleus distinguishable only with difficulty; no 
starch or oily substances could be detected. Each individual, when it 
has attained its full size, becomes a zoosporange, the zoospores being 
formed, with great rapidity, by successive bipartitions of its contents. 
The zoospores are quite naked, without any pigment-spot or pulsating 
vacuole, but with a remarkably active power of movement by means of 
* Joiira. de Bot. (Morot), iii. (1889) pp. 274-6, 284-8 (6 figs.), 
t Cf. this Journal, 1889, p. 786. X Ital. Micr., i. (1889) pp. 60-70. 
