646 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Observations on Gymnoasceae.*- — E. Dale has grown and watched 

 the development of three species of Gymnoascus. She gives a historical 

 account of this and neighbouring genera, and records the results of the 

 various cultures made. She finds that in G. Reesii the fructifications 

 arise on aerial tufts of hyphaa. The origin and growth of the sexual 

 cells is followed throughout. They are at first uni-nucleated, but at 

 the time of fusion they contain large numbers of nuclei. These pass 

 over into the ascogenous cell, and from it arise the fertile branches, the 

 tips of which swell out to form the asci. No conidia were formed in 

 this species. In G. setosus the ascospore on germination puts out one 

 or two germ-tubes which branch and immediately form conidia by 

 budding. No other form of fructification was observed in the artificial 

 cultures. G. candidus also germinated readily and fruits were produced 

 as well as oidia. The writer discusses the connection between Gymno- 

 ascus^and allied genera. 



Cytology of Yeast.f — A. Guilliermond winds up his account of the 

 nuclei of yeasts by a more definite account of the metachromatic cor- 

 puscles. He mentions the different workers who have published any 

 account of them with special reference to Marx and Worthe's theories 

 as to their significance in bacteria. He details their reaction to stains 

 and to various chemical reagents. In discussing their function, he 

 rather inclines to consider them reserve-bodies. A full bibliography 

 of the series of papers is appended, and a description of the plates that 

 appeared with the previous chapters. 



Observations on the Vitality of Yeast. :}: — H.Will furnishes further 

 data as to the preservation of yeast in the charcoal and asbestos used 

 in connection with brewing. They were again tested after a lapse of 

 1G years and 3 months. The charcoal had been invaded by moisture 

 and was spoilt for experiment. From the asbestos only wild yeasts 

 were developed. The writer discusses the influence of moisture and 

 temperature on the preservation of the yeast plant. 



Yeast Forms, &c.§ — W. Henneberg writes on the two yeasts, 

 Race II. and XII. that are much used in distilleries. He notes the dis- 

 tinguishing features of the two on the culture plates : the first growing 

 in smooth slightly convex groups ; the other in coral formation, hollow 

 at the centre. The distinctions between the two appear in solutions, 

 and they are also easily recognised under the Microscope. 



M. Hartman || found Torula colliculosa sp. n. among dried yeast 

 from Java. It formed in cultures small elevations composed of larger 

 cells than the rest of the growth. These large cells had the power of 

 causing fermentation of maltose. Young cultures that had not yet 

 produced these large cells could not induce such fermentation. The 



* Ann. Bot., xvii. (1903) pp. 570-96 (2 pis.). 



f Rev. Gen. Bot., xv. (1903) pp. 166-85. 



i Zeitschr. Gesell. Brauerw., xxvi. (1903) pp. 57-8. See also Centralbl. Bakt., x. 

 (1903) p. 251. 



§ Zeitschr. Spiritusindust., No. 9 (1903) pi. i. See also Centralbl. Bakt., x. 

 (1903) pp. 353-4. 



|| Wochenschr. Biauer., xx. No. 11, pp. 113-14. See also Centralbl. Bakt, x. 

 (1903) pp. 463-4. 



