420 SUMMARY OF CURRENT RESEARCHES RELATING TO 
Sclerotinia.* * * § — Herr R. Aderhold describes in detail the structure, 
development, and mode of propagation of the “ Vermehrungspilz,” so 
destructive especially of gardeners’ cuttings. He regards it as a Peziza 
belonging to the form Sclerotinia , and nearly allied to S. sclerotioram. 
Sooty Mould of Citrus. — Mr. D. McAlpine f has determined the 
cause of the disease of various species of Citrus in Australia known as 
sooty mould to be a hitherto undescribed fungus which he names 
Capnodium citricolum. It is a polymorphic species, having Torula, Conio- 
thecium, and Heterobotrys-stages. There are two different kinds of 
hyphee — thin-walled, colourless or slightly coloured ; and thick -walled, 
distinctly coloured. The colourless hyphse produce conids, gemmte, aud 
glomerules ; the coloured hyphae produce conids and gemmae, also sper- 
mogones, pycnids, and peritheces. The fungus is saprophytic, living 
on the sweet excretion from scale-insects, and its spread has been 
materially promoted by the destruction of honey-eating birds. 
Mr. H. J. Webber,| on the other hand, attributes the “ sooty mould ” 
so destructive to the orange crop in Florida, to two species of Pyre- 
nomycetes, Meliola Penzigi and M. Camellise . These fungi are also 
saprophytes, deriving their nourishment entirely from the honeydew 
secreted by certain insect pests, which the fungus invariably follows. 
The most destructive of these insect pests is the mealy-wing, or white 
fly, Aleyrodes Citri ; and the author describes another fungus, Aschersonia 
Aleyrodis, which is parasitic on the larva and pupa of this insect. The 
principal reproductive bodies of the Meliola are conids, pycnids, stylo- 
spores, and peritheces. 
Parasitic Fungi. — MM. E. Prillieux and Delacroix § find a disease 
of mulberry trees in European Turkey to be due to the attacks of Scle- 
rotinia Libertiana, which forms sclerotes in the branches. 
A parasitic fungus which attacks the stems of many cultivated 
orchids, is determined by M. M. Mangin || to be Gloeosporium macropus. 
Under the name Acremoniella verrucosa sp. n., Sig. F. Tognini If 
describes a parasitic fungus destructive of the haulms of wheat and 
oat. 
Miss M. E. Olson ** has found a parasitic fungus on the leaves of 
Selaginella rupestris, belonging to the family Acrospermaceae, which oc- 
cupies an intermediate position between the Pyrenomycetes and the 
Discomycetes. It is named Acrospermum urceolatum sp. n. 
Mr. H. T. Soppitt || confirms his previous statement that Puccinia 
Diagrapliidis developes its aecidioform only on Convallaria majalis. 
* Minks’ s Microgonids.|| — Dr. A. Minks makes a vigorous reply to 
Darbishire’s criticisms on his theory of microgonids. He charges his 
critic with misrepresentation, with misinterpretation of observed phe- 
* Gartenflora, xlvi. (1897) pp. 114-26 (1 pi.). See Bot. Centralbl., lxx. (1897) 
p. 166. f Proc. Linn. Soc. N.S. Wales, xxi. (1896) pp. 469-99 (12 pis.). 
J Bull. No. 13 U.S. Department of Agriculture (Div. Veg. Phys. et Patk.^ 
1897, 34 pp. and 5 pis. 
§ Comptes Rendus, xxiv. (1897) pp. 1168-70. U Tom. cit., pp. 1038-40. 
*[ Rend. r. 1st. Lomb. sci. e lett., xxix. (1896) 4 pp. See Bot. Centralbl., lxx, 
(1897) p. 168. ** Bot. Gazette, xxiii. (1897) pp. 367-71 (1 pi.). 
tt Zeitschr. f. Pflanzenkr., vii. (1897) pp. 8-10. See Bot. Centralbl., lxx. (1897) 
p. 200. Hedwigia, xxxvi. (1897) pp. 177-89. Cf. this Journal, 1895, p. 665. 
