728 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Fungi. 

 (By A. Lorbain Smith, F.L.S.) 



Two Conidia-bearing Fungi.* — A. F. Blakeslee has succeeded by 

 his method of cultivating different strains of Mucors in close proximity, 

 in inducing the development of zygospores in many forms in which they 

 were rare or altogether unknown. He applied the same method to 

 Cunning hamella echimdata, a conidial fungus that had been tentatively 

 placed in the Mucorini by Thaxter. The production of zygospores 

 decided the systematic relationships and justified the classification pro- 

 posed. He also describes a new genus, Thamnocqihalis, probably also 

 one of the Mucorini ; it bears a " bushy crown of branched fertile hyphae 

 terminated by sterile hyphge." The spores are borne on spherical heads, 

 not unlike Gunninyhamella. 



Disease of Haricot Beans.f — L. Petri found that the fungal attack 

 was due to ScUrotinia Libertiana, and was confined to the pods. The 

 fungus causes alteration and distortion of the tissues affected. The 

 author does not think that the germinating ascospore could attack a 

 healthy vegetable, but probably it lives first on any plant remains, such 

 as withered petals, etc., that may be adhering to the beans, and the 

 fungus is thus enabled to get a start, and later to attack the living plant. 



Witches' Broom on Pear Trees.J — F. Muth describes a case of this 

 disease on a wild pear. The " brooms " were unusually large, reaching a 

 height of 2 metres, and when present in large numbers they killed the tree. 

 The leaves borne on the " broom " were smaller and paler than normal 

 leaves, and flowers were less freely produced. Mycelium was found in 

 the branches, but no fruit form was seen. Another disease of pear-trees 

 resulting in abnormal growths, splitting and canker formation was 

 examined, but no fungal fruit was found. 



Botrytis Disease of Tulips and Lily of the Valley .§ — H. Kle- 

 bahn finds two kinds of sclerotia in the diseased tulips. There is a 

 small form which is accompanied by Botrytis. Plants infected by this 

 form produced Botrytis parasitica on the leaves. It does not seriously 

 injure the plants. The second form, which he calls Sclerotium tuhparum, 

 is larger, and develops on the diseased bulbs and in the adjacent soil. 

 No other fungus form was found connected with these larger sclerotia, 

 merely mycelium, and again sclerotia. Klebahn also describes a disease 

 of lily of the valley due to Botrytis cimrea, and he gives an account of 

 infection experiments with forms of Botrytis, which indicated some 

 degree of specialisation in the fungus. 



Biology of Entomophytes.|| — Marcel Mirande publishes a study of 

 the fungi that live on insects. By chemical tests he establishes the pre- 



* Bot. Gazette, xl. (1905) pp. 161-70 (1 pi.). 



t Bend. K. Accad. Lincei Roma, Nov. 1904, pp. 1-4. See also Bot. Centralbl., 

 xcix. (19(15) p. 67. 



X Naturwiss. Land. Forstw., iii. (1905) pp. 64-76 (13 figs.). See also Bot. Cen- 

 tralbl., xcix. (1905) p. 194. 



§ Jahrb. Hamb. Wiss. Anst, xxii. (1904) Beiheft 3. See also Bot. Centralbl., 

 xcix. (1905) pp. 138-9. || Rev. Gen. Bot., xvii. (1905) pp. 304-12. 



