i8o TEXT-BOOK OF FUNGI 



by members of the genus Bactridium. Cordyceps capitata 

 and C. ophioglossoides are parasitic on species of Ela- 

 phomyces. 



In the Uredineae Tuberculina persicina is a parasite on 

 various aecidium-forms, and Darluca filum infests sori of 

 uredospores and teleutospores. 



Among Basidiomycetes parasites are of frequent occur- 

 rence. Hypomyces, an ascigerous genus, occurs on various 

 Agarics, Polyporus, Boletus, Stereum, etc. Boletus para- 

 siticus grows on Scleroderma vulgare. Pleospora clavari- 

 arum occurs on various species of Clavaria. 



Numerous fungi are parasitic on the apothecia and 

 thallus of Lichens ; these have been dealt with in detail by 

 Zopf. 



Zopf, Nova Acta Nat, Cur., 70, p. 99 (1897). 



PROTECTION OF FUNGI AGAINST SNAILS 



Ludwig has obtained a red colouring matter from 

 Synchytrium galls on Anemone nemorosa, which is readily 

 soluble in water, and proves to be identical with antho- 

 cyanin. This substance is a derivative of tannin. He 

 raises the question as to whether this substance is a purely 

 pathological product, or whether it serves to protect the 

 fungus against snails ; pointing out StahPs researches, 

 which show how snails avoid plants producing tannin. 



Ludwig, Verh. bot. Ver. d. Prov. Brand., 31, p. 7. 

 Stahl, ' Pflanzen und Schnecken, '/<?# Ztg. fiir Natur 

 und Medizin, 22, N.F. xv., 1888. 



