366 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
motlier-cell becoming a pyriform or spheroidal zoosporange, containing a 
large number of biciliated zoospores, arranged upon its wall, the very 
long cilia projecting through apertures in the cell-wall, and attached by 
a narrow stalk to some filamentous freshwater alga. The gonids 
ultimately escape either through the rupture of the cell-wall or its 
dissolution, and swim about by means of their cilia. Apiocystis occurs 
also in a ccenobial phase, the coenobe, which frequently contains only 
two zoospores, becoming detached, and swimming about within the 
zoosporange. These coenobes are motile by means of exserted cilia 
proceeding from the zoospores, similar to those of the fixed zoosporange. 
Three distinct resting-stages, a Palmella, a Gloeocystis, and a Botryococcus 
phase, are also described. 
When in the fixed state, the cilia of Apiocystis are perfectly motionless, 
and the author regards the genus as a degenerate type of Volvocineoe, 
which has exchanged its mode of life as a motile coenobe moving about 
with great rapidity by its powerful cilia, for an attached existence in 
which the cilia have become atrophied. Its nearest allies will be 
Pandorina and Borzi’s Physocytium. 
Nematophyton.* — Prof. D. P. Penhallow describes five species of 
this genus of fossil algae from the Devonian strata of Canada, some of 
which have been placed in the genera Prototaxites, Nematophycus, 
Nematoxylon, and Celluloxylon. He describes the genus as consisting of 
plants with arborescent form from a branching root-like base ; the stem 
branching, often exceeding an inch in diameter, composed of unjointed 
interlacing structureless cells, which branch into an intercellular system 
of small and elosely woven filaments. 
Fungi. 
Development of Ascomycetes.t — Herr H. Zukal describes a series 
of observations on a number of Ascomycetes, including several new 
species, viz. Melanospora coprophila, M. fallax, Penicillium luteum, and 
Byparohius pachyascus. From the history of development in some of 
these species he establishes a close phylogenetic connection between 
certain species of Ascoholus and Peziza, and the Mucorini which are 
destitute of a columel. In another section of the Ascomycetes, including 
the Tuberaceae, Dothidese, and many Perisporeae and Pyrenomycetes, 
the wall of the receptacle appears as a modified mycele or thallus, from 
which there may be developed either microconids (in the spermogones), 
megaconids (in the pycnids), or asci. 
In the ascogenous hyphae of the Sordarieae, the author recognizes in 
the first instance a physiological apparatus, which serves chiefly for 
supplying the asci and ascospores with protoplasm and other nutrient 
materials. The organism hitherto described as autonomous under the 
name Helicosporangium parasiticum (Karst.), as a parasite upon Melano- 
spora leucotricha, he has now determined to be a peculiar kind of sclerote 
belonging to the latter species, which he calls a microsclerote. It is, 
in fact, a receptacle modified by unfavourable vital conditions, and 
* Trans. Roy. Soc. Canada, vii. (1S89) pp. 19-30 (2 pis.). Cf. this Journal (1889) 
p. 560. 
t SB. K. Akad. Wiss. Wien, xcviii. (1889) pp. 520-603 (4 pis.). 
