442 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
ventre fossis radicelliferis geminis percurso, carpocephalo stellato radiis 
triangularibus subtus involucra gerentibus ovata apice dehiscentia, 
archegonia complura, sed tempore maturitatis sporogonium unicum tan- 
tum foventia, sporogoniis seta longiuscula suffultis ex involucris emersis, 
periantbio nullo, capsula irregulariter quadrivalvi, elateribus valvis baud 
adhserentibus longis bispiris, sporis magnis alato-reticulatis, receptaculo 
masculo e frondis sinu orto brevissime pedunculato crasse disciformi, 
subtus radicellis et squamis ventralibus velato. Wiesnerella is inter- 
mediate between Lunularia and Dumortiera. 
Jungermannia orcadensis.* * * § — Herr E. Jorgensen lias examined both 
male and female plants of tbis liverwort (from West Norway), and pro- 
poses to establish from it a genus Anastrepta , distinguished by its convex 
leaves with recurved ventral portion, its large involucral ampbigasters, 
and its compressed perianth. 
Characese. 
Nuclear Division in the Characese. f — From an examination of a 
number of species of Char a and Nitella, Herr 0. Kaiser finds the size 
and form of the resting nucleus to be subject to very great variation. 
The mode of division is, however, always the same in the apical, segment, 
nodal, and marginal cells, in the nodal cells of the cortical lobes, in the 
antherids, and in the young oogones ; it is always karyokinetic. In the 
segment-cells, especially in those of the so-called leaves, the aster, meta- 
kinesis, and diaster stages differ from those in the other nuclei which 
divide karyokinetically ; we find the “ barrel-karyokinesis.” All the 
spindle-figures in the apical, nodal, cortical, and marginal cells are re- 
markably large, and the achromatic spindle-fibres are strongly curved 
outwardly. Centrosomes occur both in the resting nucleus and also in 
the various stages of division. In the internodal cells and those of the 
enveloping tubes of older oogones, the division of the nucleus takes place 
by fragmentation. The nuclei of the internodes which are formed in this 
way are remarkably rich in chromatin substances ; this is not so much 
the case in those of the enveloping-tubes of the oogone. Only in older 
internodes, and in the cells of the enveloping tubes of older oogones, are 
several nuclei found ; in all other cells there is only one. Granules 
occur in all the cells. 
Characese of Hungary.f — Dr. F. Nandor gives a monograph of the 
species of Characese found in Hungary, with some descriptive details of 
general structure. With regard to the systematic position of the group, 
he is strongly of opinion that they must be included in the section 
Chlorophycese of Algae. 
Algae. 
Cell-Wall of Algse.§ — M. C. Sauvageau has tested the action of 
various reagents on the cell-wall of Phseosporese ( Ectocarpus fulvescens)> 
and finds that they indicate a cellulose-pectic character. The external 
* Bergens Mus. Aarb., 1895, No. 18, pp. 1-6 (1 pi.). See Bot. Centralbl., Ixvi. 
(1896) p. 120. f Bot. Ztg., liv. (1896) l t8 Abt., pp. 61-79 (1 pi.). 
X 4 Die Characeen, mit besonderer Eiicksicht auf d. in Ungarn beobachteten 
Alien,’ Buda-Pest, 1895, 129 pp. and 5 pis. 
§ Comptes Rendus, cxxii. (1896) pp. 896-7. 
