540 SUMMARY OF CURRENT RESEARCHES RELATING TO 



filaments of the ozonium, cuticular filaments resembling those of 

 ordinary sclerotia. The Coprinus, like the Lenzites and Craterellus, 

 has an ozonium or not, according to its environment ; just as other 

 sijecies of these genera have or have not sclerotia. 



Harknessia.* — The genus Harhiessia was established by M. C 

 Cooke from the only known species, H. Eucalypti, parasitic on Eu- 

 calyptus. G. Winter now describes a second species, H. Molleriana, 

 also parasitic on Eucalyptus in Portugal, and which he regards as 

 identical with Speggazini's Melanconium uromycoide from the Argentine 

 Eepublic. Winter now proposes the following amended diagnosis for 

 the genus-: — Perithecia iutegra, pseudo-parenchymata, moUia ; sporse 

 ellipticPB, unicellulares, coloratfe, pedicello articulato hyaline prseditae, 

 demum in cirrhis atris expulsse. 



Lophiostoma caespitosum.t — S. Schulzer von MUggenburg has 

 found this rare pyrenomycetous fungus on dead branches of the haw- 

 thorn. It occurred in two diflerent forms ; one had the typical form 

 of Lophiostoma ; the other, that of Melogramma, parasitic not on the 

 wood, but on the inner bark. The fructification of the two forms is 

 identical. It follows that the two kinds of stroma among the Pyre- 

 nomycetes, those characteristic of Valsa and of Diatrype, cannot be 

 taken as distinguishing characters of families or even of genera. 



Oidium albicans.^ — According to F. A. Kehrer this fungus con- 

 sists of two elements, filaments constituting a mycelium, and small 

 toruloid structures, the conidia. The former consists of a variable 

 niimber of cylindrical cells, with lateral or terminal buds or branches ; 

 they are never composed of long unseptated tubes. The cylindrical 

 cells are not unfrequently slightly swollen at the extremities, and 

 somewhat constricted at the septa ; they are of variable length, and 

 about 0*025 mm. diameter. They are sharply defined, and when 

 young the contents are quite clear ; vacuoles and granules appear in 

 them later. The buds or conidia are produced by budding either at 

 the extremities of the filaments or near the septa, rarely at the middle 

 of a cylindrical cell. They are globular or oval, and are formed in 

 moniliform rows or in smaller or larger groups. At first simple, they 

 may give rise to other buds by simple budding. They have a clearly 

 defined outline, and the contents are slightly coloured. Instead of 

 producing other buds, these conidia sometimes develope into cylindrical 

 cells, giving rise to mycelia with lateral branches. The resting- 

 spores are formed in the globular lateral buds of the mycelium, by 

 the homogeneous strongly refractive protoplasm contracting into a 

 central ball. 



The author gives lists of nutrient fluids which are more or less 

 favourable, injurious, and destructive to the growth of the fungus. 

 He believes it to be both saprophytic and parasitic in its nature.. 



* Hedwigia, xxii. (1883) pp. 19-21. 

 t Oesterr. Bot. Zeitschr., xxxiii. (1883) pp. 113-5. 



X Kehrer, F. A., ' Ueber den Soorpilz,' 71 pp., Heidelberg, 1883. See Bot. 

 Centralbl., xiv. (1883) p. 48. 



