ZOOLOGY AND BOTANY, MICBOSCOPY, ETC. 
451 
New Genera of Hepaticae.* — Among material from tlie interior of 
China, Dr. C. Massalongo describes two new genera of Hepaticae : — 
Ascidiota g. n. Habitus sp. gen. Madothecse simulans ; caulis pin- 
natim ramosus ; folia incuba, ovato-subreniformia, subtus in lobulum 
conduplicato-appendiculata ; lobulus folio multo minor, oblongus, ad 
plicam inferne scrotiformis saccatus, ejusdem margine interno ad basim 
juxta caulem in auriculam inflatain revoluto ; areolatio speciosa, scilicet e 
cellulis utraque superficie folii eleganter subhemispherico-prominentibus ; 
foliola oblonga, optime evoluta, utrinque ad insertionem turgide-auri- 
culata ; perichaetium 1-2-jugum, terminale ; bracteae et bracteolee inter 
se liberae ; flores fern, oligogyni. 
Hariotella Besch. et Mass. ( Lepidolsense subgen. Hariotella Schiff.). 
Habitus sp. gen. Polyoti ; caulis pinnatim ramosus ; folia incuba, imbri- 
cata, subtus auricula praedita ; foliola bidentata, dentibus saepe in 
auriculas transformatis ; perichaetium polyjugum, in rarnulo brevi laterali ; 
bracteis et bracteolis imbricatis, subobovato-oblongis fluentibus, interior- 
ibus in sacculum colesuheformem oblongum liberum et infiatum con- 
nectis ; flores fem. 9-12-gyni ; calyptra e basi ad medium cum sacculo 
colesulaeformi accreta. 
Systematic Position of Monoclea.j — Prof. D. H. Campbell advo- 
cates the removal of Monoclea from the Jungermanniaceae, and placing 
it among the Marchantiaceae. The form of the thallus and the character 
of the apical cell correspond with those of Marchantici ; the most im- 
portant divergence from the Marchantiaceae being the absence of the 
ventral scales, which are, however, represented by short-lived papillate 
hairs. Unlike the Jungermanniaceae, Monoclea has two kinds of root- 
hair, thin- walled and thick-walled. The structure and arrangement of 
the sexual organs is altogether that of the Marchantiaceae, among which 
it presents the greatest affinity with the Targionieae. There are six 
rows of neck-cells, in contrast with the five of the typical Jungermanni- 
aceae. 
Retrogression in Metzgeria.J — Among normal plants of Metzgeria 
furcata Prof. K. Goebel finds others, in an enfeebled condition owing to 
unfavourable vital surroundings. This condition has been described as 
the var. ulvula. These plants have a strong tendency to revert to a 
“young condition” in which there is an apical cell which does not 
further divide. In certain cases, the reversion may even proceed further, 
and the thallus be reduced to a single row of cells. These degraded 
structures produce adventitious shoots, resembling the parent shoot, 
which is never the case with the normal Metzgeria thallus. 
Algae. 
Influence of Algae on the Purity of Water. § — From experiments 
made on the drinking-water of Hamburg, Herr 0. Strohmeyer concludes 
that the green algae — Spirogyra, Cladophora, Enteromorpha , Stichococcus 
* Nuov. Giorn. Bot. Ital , v. (1898) pp. 255-GO. 
f Bot. Gazette, xxv. (1898) pp. 272-4. 
t Flora, lxxxv. (1898) pp. 69-74 (5 figs.). 
§ ‘ Die Algenflora d. Hamburger Wasserwerkes,’ Leipzig, 1897, 48 pp. See Bot. 
Centralbl., 1898, Beih., p. 406. 
