ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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v. subpyriformes, saepe curvatae ; membrana cellularum crassissima et 
insigne lamellosa ; contentum cellularum granulosum. Incrementum 
plantarum bipartitioue cellularum intercalari. Under Ulotrichaceae. 
Temnogametum. Cellulae vegetativae ut in Mougeotia, cylindricae, 
cbromatophoro elongato complanato, pyrenoidibus uniseriatim dis- 
positis. Propagatio zygosporis, conjugatione scalariformi lateralive 
cellularum brevium specialium abstrictarum format's. The type of a 
new family of Conjugate, Temnogametacea:, characterised by the con- 
jugation taking place only between cells specially abstricted. 
Pyxispora. CellulaB vegetativae ut in Zygnema, conjugatione scalari- 
formi ; zygosporae tubam conjugantem totam inter filamenta complentes ; 
zygosporas e parte solum contenti cellularum formatae, elliptico-oblongae 
v. ellipsoid ae, cum porca cingente in planitie diametrorum brevissimorum 
et rima circumscissa secundum porcam. Under Zygnemaceae. 
Ichthyocercus, Cellulae cylindrico-fusiformes, subelongatae, ad medium 
leviter constrictae ; a fronte visae lateribus subparallelis, apicibus basibus- 
que semicellularum in latitudine subaequalibus (nonnunquam apicibus 
paullo angustioribus v. paullo latioribus), depressione late minime pro- 
funda ad apices per latitudinem totam, spina brevi leviter divergente 
ad angulum unumquemque instructae ; a vertice visae subcirculares. 
Among Desmidieae, near Teimemorus and Enastrum. 
Athroocystis. Planlae aquaticae, familias parvas formantes, in strato 
denso pulverulento aggregatas ; familiis e cellulis numerosissimis com- 
positis, intra tegmentum tenuissimum firmum non mucosum dense 
confertis. Propagatio ignota. Placed in Palmellaceae. 
Conjugation of two Zygotes.* — Herr C. P. Lommen has observed 
the conjugation with one another of two zygotes in a fertile filament of 
a Spirogyra sp. 
Calcareous Algae.f — Miss J. E. Tilden enumerates and describes 
the algae which live in a calcareous or siliceous matrix found in Min- 
nesota. One side of a tank was found to be covered by a calcareous 
incrustation exhibiting various colours, and permeated by three algae 
(Protophyta) belonging to the Cyanopliyceae, Dicliothrix calcarea , Lyng- 
bya martensiana calcarea , and L. nana. With them is associated a fungus 
corresponding to the chlamydospore- filaments of PseudoJielotium granulo- 
sellum. The other three sides of the tank were covered by a coating of 
Chaetophora calcarea , together with a Lyngbya, the two appearing to carry 
on a kind of symbiotic existence. The five algae have apparently, either 
alone or in combination, the power of causing the precipitation of 
calcium carbonate from the water. On white sandstone cliffs above the 
Mississippi river, and imbedded in the rock to the depth of at least 
half an inch, was found another remarkable alga, ScMzothrix rupicola. 
Chlorogonium.* — Herr R. H. France describes the structure of this 
little known genus of Algae. The chromatophores form, in the simplest 
case, a regular or irregular annular band, which may split into a single 
or double spiral. The chromatophores of the swarm- cells and those 
* Arcli. Mikr. Anat., xlix. (1897) p. 462 (1 fig). 
t Bot. Gazette, xxiii. (1897) pp. 95-104 (3 pis.). 
i Termeszetrajzi Fuzetek, xx. (1897) pp. 287-308 (1 pi.). See Bot. Centralbl., 
lxx. (1897) p. 197. 
