ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
521 
protoplasm, which move about in the water with a jerking motion, then 
come to rest, and invest themselves with a coat of cellulose. V. sessilis 
var. csespitosa was observed to form in its ordinary filaments thick 
gelatinous septa which remained suspended in the water after the rest 
of the filament had disappeared. 
Dictyosphseria.* — Mr. G. Murray discusses the structure and sys- 
tematic position of this genus of siphoneous algae, and adopts the com- 
monly accepted view of its close alliance with Valonia and Anadyomene, 
among the Valoniaceae. 
Fossil Caulerpa.f — Under the name Caulerpa Carruthersii Mr. G. 
Murray describes a fossil alga from the Oolite (Kimmeridge Clay of 
Weymouth), hitherto regarded as an Equisetaceous plant. It appears 
to be nearly allied to the existing Caulerpa cactoides. 
Chlorella, Chlorococcum, and Chlorosphsera.J — Prof. A. Hansgirg 
is of opinion that Beyerinck’s genus of Schizophyceae Chlorella must be 
reunited with Chlorococcum , the absence of zoospores not being a cha- 
racter of sufficient constancy to justify the separation ; and, furthermore, 
that both these genera must be sunk in Protococcus, of which he makes 
two sections — Chlorococcum, of which the species are aquatic, and Eu- 
protococcus, which includes the aerial forms. Beyerinck’s Chlorosphsera 
is hardly distinguishable from Pleurococcus , and C. angulosa is certainly 
identical with Pleurococcus angulosus. 
Fungi. 
Rabenhorst’s Cryptogamic Flora of Germany (Fungi). — Parts 
47-50 of this work continue the account of the Phycomycetes, under 
the editorship of Dr. A. Fischer. The description of the Chytridiaceae 
is completed with the family Hyphochytriaceae or Cladochytriaceae, made 
up of the genera Cladochytrium (18 species), Amcebochy trium , Catenaria, 
and Hyphochytrium. A list is appended of the species of animals and 
plants on which the various Archimycetes are parasitic. 
The whole of the Zygomycetes are included in these parts. The 
account commences with a very full description of the structure of the 
Mucorinae, which are divided into four families, the Mucoraceae and 
Mortierellaceae, in which the nonsexual propagation is by means of 
motionless spores inclosed in sporanges ; and the Chaetocladiaceae and 
Cephalidaceae, in which it takes place by conids borne on conidiophores. 
The Mucoraceae include the genera Mucor (22 species, several of them 
new), Circinella , Pirella, Phycomyces, Spinellus, Sporodinia , Bhizopus 
(7 species, 1 new), Absidia, Thamnidium, Chsetostylum, Helicostylum, 
Dicranophora, Pilaira, and Pilobolus (7 species). The Mortierellaceae 
are made up of the genera Mortierella (14 species), and Herpocladium ; 
the Chaetocladiaceae of the single genus Chsetocladium ; the Cephalidaceae 
of Piptocephalis (8 species), Syncephalis (17 species), and Syncephal- 
astrum. 
Next follow the Oomycetes, of which we have in these numbers a 
complete monograph of the German species of the first order, the Sapro- 
* Phycol. Mem. (Murray) i. (1892) pp. 16-20 (1 pi.). 
f Tom. cit., pp. 10-15 (2 pis.) 
i SB. K Bohm. Gesell. Wiss., 1891, pp. 298-9. Cf. this Journal, 1891, p. 232. 
