310 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Penieillium as a Wood-destroying' Fungus.* — Prof. H. Marshall 
Ward finds Penieillium to be a much more active organism in initiating 
and carrying on the destruction of wood than has hitherto been supposed ; 
it does not arise merely as the result of the disintegration of the tissues 
by other Fungi. 
Structure of the Hemiasci.t — From a study of the development of 
several genera and species of the Hemiasci — especially Ascoidea rube- 
ecens, Protomyces Bellidis , and P. macrosporus — Herr C. M. L. Popta 
arrives at the conclusion that, as far as regards the mode of spore-for- 
mation, they do not form a well-differentiated group ; some genera, 
represented by Ascoidea } showing greater affinity to the Ascomycetes, 
others, e.g. Protomyces, to the Phycomycetes. In Ascoidea, the numerous 
and minute spores are imbedded in a matrix ; the entire mass escaping 
through an opening in the apex of the sporange in long vermiform coils. 
In Protomyces, on the other hand, there is no such matrix in which the 
spores are imbedded ; they are expelled with considerable force in a 
globular mass through the opening in the sporange. The fusion of 
spores which takes place in Protomyces macrosporus does not appear to 
be accompanied by any fusion of nuclei. 
Ascoidea agrees with the Ascomycetes in its free spore-formation, 
leaving an unused matrix, but differs in the development of its sporange 
with several nuclei. In these points Dipodascus and Conidiascus agree 
with Ascoidea. 
Development of the Helvellineae.J — Dr. G. Dittrich has followed 
this out, especially in the cases of Mitrula phalloides and Beotia gelatinosa. 
He regards the Helvellineee as Pezizese with a strong growth in surface 
of the hymenium, the variability of their perithece probably ‘depending 
p>artly on external conditions. The primary nucleus of the ascus is 
formed (in Helvetia infula ) by the fusion of two nuclei, a purely vege- 
tative process. 
The fructification of 31itrula phalloides presents, at its first origin, a 
non-sexual sterile mass of tissue formed of branched and interwoven 
mycelial shoots, in which the fertile elements arise as groups of cells 
with abundant protoplasm and large nuclei. These are pushed up to 
the upper part of the fructification, where the peripheral hyphae form a 
mucilaginous envelope, among which the paraphyses become diffe- 
rentiated. This is the origin of the angiocarpous hymenium. A similar 
process takes place in Leotia gelatinosa , but here the paraphyses are 
already differentiated in the unstalked fructification. The paraphyses 
break through the envelope, while the ascogenous hyphae beneath them 
branch freely. In Helvetia Ephippium the fertile disc, which is at first 
hemispherical, becomes two-lobed by the strong superficial growth of 
the upper side. The irregular growth and strong curving of these lobes 
gives rise to the complicated pileus of species of Helvetia and Gyromitra, 
and finally to the simpler forms of Peziza. 
Biology of Parasitic Fungi.§ — Herr M. Nordhausen has investi- 
gated the conditions under which Botrytis cinerea — under ordinary con- 
* Ann. of Bot., xii. (1898) pp. 565-6. f Flora, lxxxvi. (1899) pp. 1-46 (2 pis.). 
X Beitr. z. Biol. d. Pflanzen (Cohn), viii. (1898) pp. 17-52 (2 pis.). Cf. this 
Journal, ante, p. 65. § Jahrb. f. wiss. Bot. (Pringsheim), xxxiii. (1898) pp. 1-46. 
