764 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
and to place them in the Chlorophyceae, near to Hieronymus’s group of 
Glaucocystideae.* * * § 
Halicystis and Valonia.j — Mr. G. Murray has discovered Halicystis 
ovalis as a British plant, and is disposed to remove the genus from the 
Siphonocladaceae to the Siphoneae. Its vegetative structure recalls that 
of Botrydium. He further describes the hitherto unknown reproductive 
organs of Valonia ventricosa, the single cell of which is as large as a 
hen’s egg. 
Fungi. 
Fungus-gardens of Ants.f— Herr A. Moller has confirmed the 
hypothesis of Belt that certain South American ants cultivate a fungus 
on the leaves of the plants which they frequent, and live upon this 
fungus. The observations were chiefly made on four species of Atta , 
the nests of which are composed of fragments of leaves which are pene- 
trated by fungus-hyphae and form the fungus-garden. As long as the 
nest is inhabited by ants, these hyphse do not form any reproductive 
organs, but exhibit a strong tendency towards the formation of swellings 
and excrescences. When cultivated independently the fungus developes 
brown spores, and is found to belong to the Agaricineae and to the genus 
Bozites, and the author names it B. gongylophora. Similar nests formed 
by three species of Apferostigma , were found in a decaying pileus of a 
Pclyporus ; and two species of Cyphomyrmex are also breeders of fungi. 
Relationship of the Conidial Forms of Fungi.§ — M. J. Costantin 
sums up the results of the observations of different mycologists which 
have established the fact that a number of fungi belonging to the Asco- 
mycetes, Basidiomycetes, Ustilagineae, Entomophthoreae, and Mucorineae 
go through a variety of stages of development, and asserts furthermore 
that a Cladosporium- form occurs in Pleospora, Leptosphseria, and Fumago. 
Membrane of the Oosperm of Cystopus Tragopogonis || — Herr P. 
Magnus identifies Cystopus spinulosus with C. Tragopogonis , which 
includes not only the parasites on Cirsium but also those on Scorzonera, 
Tragopogon , Filago , &c. The oosperm may be furnished either with 
long spines or with low warts. The membrane of the oosperm of this 
species presents the most complicated structure of any among the Perono- 
sporeae. 
Saprolegniacese of the United States.! — Prof. J. E. Humphrey 
publishes a monograph of the Saprolegniaceae of the U.S., which includes 
descriptions of the following new species : — Saprolegnia Treleaseana , 
Adilya americana , A. megasperma i A. papillosa, Apodachlya (?) com- 
pleta , also of a new genus Thraustotheca , formed from Dictyuchus 
clavatus. He gives a complete account of the structure and life-history 
of the order, which ho divides into two tribes, Saprolegnieae and Lepto- 
miteae. The latter is characterized by abrupt constriction of the hyphas 
* Cf. this Journal, 1892, p. 830. 
f Phycol. Mem. (Murray) ii. (1893) pp. 47-52 (1 pi.). 
X Bot. Mitthl. aus den Tropen, Heft 6 (1893) 128 pp,, 7 pis. and 6 figs. See 
Bot. Centralbl., lv. (1893) p. 92. 
§ Rev. Gen. de Bot. (Bonnier), v. (1893) pp. 84-6. 
j| Ber. Deutseh. Bot. Gesell., xi. (1893) pp. 327-30 (1 pi.). 
^ Proc. Amer. Phil. Soc., 1893, pp. 63-148 (7 pis.). 
