664 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
one pseudocilium goes to each daughter-cell, and a second is subse- 
quently formed. Similar pseudocilia were observed also in Tetraspora. 
According to the author, the enormous growth of the vesicle of Apiocystis 
(increasing 1715 times in volume) takes place neither by apposition nor 
by simple swelling, but by the intercalation of fresh substance from the 
side of the envelope. 
Fossil Algae. — Dr. A. Schenk * * * § gives an account of the fossil organ- 
isms at present known which undoubtedly belong to the Algae, from 
which he excludes Oldhamia , Eophyton , the Chondritese, and a portion 
of the Sphaerococciteae, the Fucoideae, the Spongiophyceae, the Dictyo- 
phyceae, and many others. 
Diatoms make their appearance for the first time in the upper 
Cretaceous strata ; the Bactryllia of the Trias may possibly be their 
ancestors. The cretaceous genera are identical with ours ; but the 
number of species appears to have increased enormously. The verti- 
cillate Siphonece do not appear to have existed before the Tertiary 
epoch, while the Corallineae may date from the Jurassic period. 
M. 0. Borge f has found in the glacial clays of the Isle of Gothland a 
number of fossil Desmids apparently belonging to existing Arctic types. 
Receptaculites and Bornetella.J — Dr. Rauff describes in detail the 
known species of the genus of fossil calcareous algae Bornetella, and 
compares with them the structure of Beceptaculites. He concludes in 
favour of the inclusion of this latter genus in the Siphoneae. 
Fungi. 
Effect of Parasitic Fungi on the Flower.§ — Herr P. Magnus de- 
scribes the effect of a number of parasitic fungi on the parts of the 
flower of the host-plant. Cystopus candidus on Sinapis and Brassica 
causes swelling of all the parts of the flower attacked ; while Peronospora 
violacea on Knautia arvensis , and P. Lin arise on Linaria minor produce 
no such result. Taphrina Pruni not only induces the familiar bladder- 
like swelling of the ovary, but also sometimes causes the filaments to 
swell up into a pear-like form. TJstilago antherarum incites the rudi- 
mentary stamens in the male flowers of Lychnis dioica to perfect 
development. AEcidium leucospermum produces no alteration in the 
flowers of Anemone nemorosa ; while AE. punctatum on A. ranunculoides 
causes more or less abortion in the different parts of the flower. AE. 
Magelhsenicum appears to exercise but little injurious influence on the 
development of the flowers of Berheris vulgaris. 
Effect of Poisons on the Spores of Fungi.|] — According to experi- 
ments made by Herr Wiitherlich, the spores of different fungi exhibit a 
very different power of resistance to the poisonous effects of the solutions 
of mineral salts or of acids. 124 parts by weight of cupric sulphide 
* ‘ Handb. d. Palaeontologie,’ 2 te Abth., Munich, 1890, 69 pp. See Bonnier’g 
Rev. Gen. de Bot., v. (1893) p. 186. 
f Bot. Notiser, 1892, pp. 55-8. See tom. cit., p. 188. 
t Verb and 1. Naturh. Yer. Preuss. Rheinlande, xlix. (1892) pp. 74-90 (7 figs.). 
§ Verbandl. Bot. Yer. Prov. Brandenburg, 1892, pp. vi.-viii. 
|| ‘ Ueb. d. Einwirkung v. Metallsalzen u. Sauren a. d. Keimfabigkeit d. Sporen 
einiger parasitischer Pilze.’ See Biol. Centralbl., xiii. (1893) p. 265. 
