ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 587 



concave, almost boat-shaped, arid are of an intense yellow-brown colour. 

 No other spore form was found. The paper is illustrated by photo- 

 grapbs of the diseased plants and of a microscopic section through one 

 of the warts, showing the resting spores in position. 



Energy of Assimilation in Fungi. * — T. Bokorny finds that the 

 assimilation energy measured by the relative increase in weight per unit 

 of time, is much greater for moulds and yeasts than for green plants. 

 A mould nourished with glycerol and ammonium sulphate increased in 

 weight one thousand times in tweuty-eight days. Yeast yields the 

 largest crop in presence of cane-sugar when its nitrogenous food is 

 peptone, asparagine is less favourable, and ammonium sulphate is least 

 of all. Spirogyra can assimilate its carbon from sodium formaldehyde 

 sulphonate in absence of carbon dioxide, starch being formed in the 

 cells ; 0-07 grm. of the dried alga gave about 0*11 grm. in 5 days. 



Zymase in Fungal Hyphee.j — M. Maze has experimented with the 

 hyphae of Eurotiojms Gayoni, in order to decide the prt sence of zymase 

 in the cells that are largely exposed to the air, and to prove that the 

 quantity of this substance in a given weight of mycelium diminishes 

 with the age of the fungus. His method was, by the employment of 

 ether and alcohol, to kill the mycelium while at the same time he fixed 

 the diastase. He then pounded the mycelium and tested it in a solution 

 of glucose. He found that aerobic life was necessary for the production 

 of zymase and that it is rapidly destroyed as the filaments become old. 



Pleomorphism and Chlamydospore Formation among Filamentous 

 Fungi. I — 0. Brefeld discusses at some length the evolution of the 

 higher fungi from the [lower. He traces the development of conidia 

 and sporangia, the latter through the Hemiasci to the fully developed 

 Ascomycetes, the former to the Basidiomycetes. He describes the 

 growth of a new form of Chlamydomacor which appeared in a culture of 

 Ptychogaster spores. After a period of luxuriant growth the contents 

 of the filaments centred in definite small areas, which were cut off by 

 cell-walls from the rest of the mycelium. These enriched portions 

 acted as resting-spores and after a quiescent period of four to six weeks 

 they produced sporangiophores ami sporangia, or, if they were very 

 small, a new vegetative growth. Brefeld compares this type of de- 

 velopment with the well-known Mucor racemosus and classes them both 

 in Chlamydomucor. He claims also that he finds an exactly similar 

 chlamydospore formation among the higher fungi. He reiterate, his 

 frequently expressed opinion that sexuality exists only among the lower 

 al^a-like fungi, that the higher are derived from the non-sexual conidia 

 and sporangia of the lower fungi, and that sexuality is therefore not to 

 be found in such. He refuses to recognise any connection between them 

 and the Floridese. 



The Saprolegnieae.§— M. V. Minden publishes a general account of 

 this family. He compares them with the nearly related groups of algae, 

 and notes the points of resemblance, as, for instance, between Mono- 



* Pfliiger's Arehiv, lxxxix. (1902) pp. 454-74. See also Journ. L'hem. Soc., 

 lxxxii. i:. p. 345. t Oomptes Bendus, exxxv. (1902) pp. L13-6. 



% Jahresber. Schles. Ges., lxxix. II. Abt., pp. 4-22. 

 § Centralbl. Bakt., 2 ,e Abt.. viii. (1902) pp. 805-10. 



