ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 479 



H. Klebahn * has investigated a fungus that attacks the bark and 

 flower-buds of Syringa. He found, in the intercellular spaces, resting 

 spores which, in their development, recalled the oospores, oogonia, and 

 antheridia of the Peronosporete, but no conidial form was found. In 

 artificial cultures he discovered that the hyphas were non-septate, but at 

 intervals a ring-shaped thickening of the wall is formed. Oogonia and 

 antheridia were also produced in these cultures. Klebahn places the 

 fungus in the Peronosporese, from which it differs in the absence of 

 conidial formation, and names it Pldmophthora Syringa g. et sp. n. 



A disease of tomatoes was found by V. Oven t to be due to Fusarium 

 erubescens sp. n. It attacks and shrivels the fruit and the stalk. The 

 fungus is a variable form, producing micro- and macrogonidia, chlamy- 

 dospores, and sclerotia. 



H. C. Schellenberg % found a number of thirty-year-old fir trees 

 destroyed on the Adlisberg. They showed a strong infection of Dasy- 

 scypha calyciformis, identical with the fungus that attacks other Conifers. 

 It is a wound parasite, and its growth is favoured by a too close planting 

 of the trees, and by a damp atmosphere. The crown branches were 

 most frequently attacked and growth was arrested. 



R. Laubert § chronicles a bad disease of Primus Padus caused by 

 ScleroUnia Padi. The fungus attacks the leaves, where it forms spores 

 which infect the opening flowers. Sclerotia are formed in the flower, 

 and in the following spring the ScleroUnia grow from the sclerotia, and 

 the ascospores re-infect the young leaves. 



J. M. Van Hook || gives an account of a serious outbreak of disease 

 of seed peas caused by Ascochyta Pisi. Stem, leaves, and pods were 

 attacked by the fungus. It grows through the husk of the pod and 

 destroys the seed. The writer describes the development of the fungus 

 and the course of the disease. He also gives methods of treatment. 

 Peas should not be re-planted on the same area, as the fungus lives on in 

 the soil or compost as well as in the seed peas. 



Myxobacteria.lF — Alfred Quehl recalls to students the work done and 

 published on these organisms, and gives us the results of his collections 

 in the neighbourhood of Berlin, and of his laboratory cultures. He has 

 the same experience as others have had, that these bacteria are nearly 

 always found on laboratory material, very rarely in the open. He 

 explains this by their fragility and their susceptibility to moisture, which 

 causes the forms to collapse. He records a large number of species 

 already found by Thaxter in North America, and he adds a number of 

 new species in the genera Polyangium and Myxococcus. He thinks that 

 the new species, Mgxococcus pyriformis A. L. Sm., the only species 

 recorded as yet for Britain, is probably a good species on account of its 



* Centralbl. Bakt., xv. (1905) p. 335. See also Ann. Mycol., iv. (1906) p. 96. 



f Landw. Jahrb., xxxiv. (1905) pp. 489-521. See also Ann. Mycol., iv. (1906) 

 pp. 96-7. 



X Nat. Zeitschr. Land. Forstw., xii. (1905) p. 512. See also Ann. Mycol., iv. 

 (1906) p. 98. 



§ Gartenflora, 1905, p. 169 (1 pi.). See also Bot. Centralbl., ci. (1906) p. 530. 



|| Obio Nat., vi. (1906) pp. 507-12. 



i Centralbl. Bakt., xvi. (1906) pp. 9-34 (1 pi. and 3 figs.). 



