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SUMMARY OF CURRENT RESEARCHES RELATING TO 
matrical portion), and fertile filaments forming a cushion of parasitic 
tissue on the external surface of the host (extramatrical portion of the 
thallus) ; antherids and procarps unknown ; tetraspores formed by 
cruciate division in radially disposed rows of tetrasporanges. 
Fertilisation of Batrachospermum.* — From an examination chiefly 
of a species from the Cameroon s, B. Bohneri , Herr W. Schmidle has 
come, on several points, to different conclusions as to the mode of fertili- 
sation in Batrachospermum from those of Davis, f The trichogynes 
occur at the ends of branches which are readily distinguished from the 
other branches of the plant. Their form varies greatly in different 
species. There is never in them any indication of a nucleus before 
impregnation. At the apex of the trichogyne is a cap of mucilage, 
which finally completely envelopes the fertilising spermatia (pollinoids), 
upon which the trichogyne exercises a powerful attracting force. In 
the species examined more than one pollinoid is absorbed by the tricho- 
gyne. Each pollinoid contains almost invariably two nuclei. When 
the pollinoid puts out its conjugating tube which enters the trichogyne, 
the anterior nucleus passes into the trichogyne, usually followed by the 
posterior one. Although the process was not actually observed, the 
author has no doubt that the actual process of impregnation consists in 
the fusion of one of the nuclei of the pollinoid with the nucleus of the 
carpogone. 
Germination of the carpospores frequently takes place while they are 
still attached to the glomerule. The position and structure of the hairs 
varies in different species of Batrachospermum , and may be conveniently 
used as a specific character. 
Fertilisation and Development of the Oospore in (Edogonium.f — 
Prof. A. N. Berlese has followed out these processes in the case of CE. 
vesicatum, in which the production of “ oospores ” has been stated to take 
place parthenogenetically. The author asserts that this is not the case, 
antherids and antherozoids being formed on special filaments distinct 
from those which bear the oogones. The antherozoids, escaping from 
the antherid, reach the orifice of the oogone ; the anterior extremity only 
of the antherozoid enters the oogone, and comes into contact with the 
oosphere. Its nucleus passes, with the cytoplasm, into the oosphere, and 
fuses with its nucleus in a true act of fecundation. 
Nereocystis.§ — Prof. C. MacMillan gives an account of the structure 
of this gigantic seaweed, belonging to the Laminariacete, the frond of 
which may attain a length of 100 metres, including the stipe. The large 
pneumatocyst or swim-bladder originates as a swelling in the stipe just 
below the lamina ; it is retort-like in form, and may attain a length of 
2-3 metres. In the stipe is a zone of sieve-tubes, which ultimately 
become extremely slender, and present somewhat the appearance of a 
thermometer-tube. The so-called trumpet-hyphae the author believes to 
have a different origin from the sieve-tubes. The splitting of the lamina 
commences with the deliquescence of a single row of cortical cells im- 
mediately below the epiderm. 
* Bot. Ztg., lvii. (1899) l te Abt., pp. 125-35 (1 pi. and 1 fig.). 
f Cf. this Journal, 1896, p. 333. 
* Kiv. Patol. Veg., vii (1899) pp. 153-66 (2 pis.). 
§ Bull. Torrey Bot. Club, xxvi. (1899) pp. 273-96 (2 pis.). 
