ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 485 



the observations on this formation do not differ from those of other 

 workers. The author does not consider the upper sterile cell as a 

 trichogyne, as it is present on all palisade rows irrespectively, or some- 

 times fails altogether : he looks on it merely as a " buffer " cell between 

 the fertile cell and the epidermis. 



Ustilago bulgarica sp. n.* — Fr. Bubak records the finding of this 

 fungus on Millet. The spore-mass is greenish-brown, and is developed 

 only in the fruit, which it changes to short horn-like bodies, the surface 

 of which is somewhat wrinkled and covered by the grey epidermis. The 

 spores are clear olive-brown, with a thin, smooth membrane. Bubak 

 supposes that the fungus may have been introduced into Bulgaria with 

 foreign seed. 



Classification of Russulse.j — R. Maire comments on the confusion 

 existing as to the determination of species of Russula ; he sketches the 

 work done on this genus by modern mycologists, and gives an account 

 of the various divisions of the genus adopted by Persoon, Fries, Quelet, 

 Massee, and Bataille. Maire has studied Russulse for some years, and ex- 

 plains his views on the subject, and his own methods of determination. 

 For general characters he studied the size, consistence, taste, odour, colour 

 and its changes, tint of spores in the mass, the different characters of 

 the stipe and gills, and, finally, the microscopic characters of the internal 

 tissues of the vegetative body, and, more particularly, of the hymenial 

 tissues and spores. Several chemical reagents have been found useful in 

 distinguishing between allied species, and their action is explained and 

 the methods of applying them. A number of species are carefully 

 described in the way considered necessary by Maire, with figures of 

 cystidia, hyphse, spores, etc. 



Armillaria mucida.f — C. E. C. Fischer undertook experimental 

 work on this fungus to decide the question of its parasitism. He failed 

 to do this, as none of the inoculations on living trees took effect. He 

 grew the fungus saprophytically on a variety of substances, and gives an 

 interesting series of notes on its growth and development. No secondary 

 spore-forms were observed. 



Geotropism and Growth in Length of Coprinus stiriacus.§ — Fritz 

 Knoll states that growth in length in the stalk of the above Coprinus is 

 brought about by the stretching of the cells, and the outer cells develop 

 more quickly than the inner. Coprinus is ageotropic, except shortly 

 before or during the shedding of the spores. 



Coniophora cerebella as Timber-destroyer. || — This fungus was found 

 by E. Schaffnit to be destroying the beams of a house in the autumn of 

 1906. It was kept under observation the following years and the devel< >]>- 

 ment of the disease was carefully followed. The wood was destroyed in 

 much the same way as by Merulius. Schaffnit found that the timber 



* 



Zeitschr. Landw. Versuch. Oesterr., xiii. (1910) p. 53. Sec also Centralbl. 

 Bakt., xxvi. (1910) pp. 695-6. 



+ Bull. Soc. Mycol. France, xxvi. (1910) pp. 49-125 (6 figs.). 

 \ Ann. Bot., xxiii. (1909) pp. 515-55 (2 pis.). 

 § SB. k. Akad. Wiss. Wien, lxviii. (1909) pp. 575-634. 

 || Centralbl. Bakt., xxvi. (1910) pp. 352-6(1 pi.). 



