776 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Peculiarity in the Root of Ceratopteris thalictroides.* * * § — M. G-. 
Poirault describes a peculiarity in this aquatic Fern. The roots pro- 
duce two series of opposite rootlets ; but sometimes the one and some- 
times the other remains intracortical. After traversing the internal 
cortex, they reach one of the lacunae in the internal cortex, and finding 
there conditions favourable to their development, they do not continue 
their growth towards the exterior, but descend vertically in the cortex 
for a considerable distance. 
Structure of the Primary Fibro-vascular System in Lepidodendron 
selaginoides.f — M. M. Hovelacque states that in the stipe of Lepido- 
dendron selaginoides two main regions can be distinguished : — (1) The 
fibro-vascular mass including the central primary xylem and a primary 
phloem-crown, between which is a zone of secondary fibro-vascular tissue. 
(2) The cortex, which may be divided into three zones. The foliar 
traces detach themselves from the primary xylem in the form of small 
circular ligneous masses, and traverse the secondary xylem horizontally. 
The primary phloem is more differentiated than that of Lepidodendron 
Harcourtii , and at the exterior consists of a pericambial zone of similar 
parenchymatous elements. 
Muscineae. 
New Genera of Mosses, Aulacomitrium and Willia. — In his enu- 
meration of all the species of Musci and Hepaticas recorded from Japan, 
Mr. W. Mitten J describes a number of new species belonging to each 
order of Muscineae, and the following new genus of Musci, — Aulaco- 
mitrium. Theca apicalis, a3qualis ; folia perichaetii in vaginam exsertam 
convoluta ; calyptra mitriformis, plicata. 
Among a large number of new species of Mosses from South Georgia, 
obtained in the German Polar Expedition, Herr C. Muller (Hal.) § 
describes a new genus and species Willia grimmioides , with the following 
generic characters, — Folia Syntrichise, sed stricta Eubarbulse , apice 
liyalino-limbata, calyptra capsulam omnino obtegens, cylindrico-campa- 
nulata, basi in lobos rotundatos incisos subinflexos hookerioideo-divisa ; 
peristomium nullum. 
Cliaraceae. 
Rabenhorst’s Kryptogamen-Elora v. Deutschland (Characeae). — 
Parts 5 and 6 of Dr. W. Migula’s monograph of the Characese commence 
with the completion of the description of Tolypellopsis stelligera. A full 
account is then given of the genus Lamprothamnus and its single species 
L. alopecuroides, and of Lychnotliamnus and its single species L. barbatus. 
There is a description of the general characters of Chara , and a schedule 
of its twenty-seven species, followed by a commencement of the descrip- 
tion of the species in detail. The letterpress is exhaustive, and the 
illustrations are of remarkable excellence. 
* Journ. de Bot. (Moron, v. (1891) p. 264. 
t Comptes Rendus, cxiii. (1891) pp. 97-100. 
x Trans. Linn. Soc. Loud. (Bot.), iii. (1891) pp. 153-206 (1 pi.). 
§ ‘ Bryologia Austro-Georgise ’ (Separat-Abdr. Deutsch. Polar Exp.), 46 pp. See 
Bot. Ccntralbl., 1891, Beib., p. 175. 
