ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 219 



Gueguen* describes his method of isolating auother pathogenic 

 Oospora from " black tongue," 0. Jingualis. From streak cultures on 

 carrot he is able to transfer minute portions containing only the one 

 organism, 



" Blindness " in Potato Tubers. f — The disease known as " blindness " 

 is so called because it more or less completely destroys the eyes, and 

 the tubers thus affected are worthless for use as seed. E. Dale has 

 proved that the mycelium of VerticiUiuni albo-atrum is present in blind 

 potato tubers, where it causes the destruction of most of the eyes. If 

 the tuber grows the mycelium grows up into the new shoots, but it is 

 generally confined to the subterranean stems, and creeps along them 

 into the newly formed tubers, internally colourless, externally a thin 

 brown mycelium. 



The disease known as " leaf -curl " is said to l)e due to the same 

 fungus. Tuliers from infected crops should not be used for " seed," 

 though they are quite fit for culinary purposes. 



Plant- diseases. — A witch-broom disease of Cacao in Surinam % has 

 been attributed to the action of various species of fungi. They cause an 

 excessive growth of lateral shoots, and when these drop off the wound 

 provides an opening for the entrance of insects or parasitic fungi. 

 The broom has been proved by J. B. Rorer to be due to CoUeMricham 

 hixificum. It attacks the young soft tissue of the developing buds and 

 young stems. 



Ed. Essed § describes malformations in the banana caused by the 

 fungus UstilaginoideUa mdipigera. The disease (Surinam disease) appears 

 as a large swelling at the base of the stems with ruptured leaf-bases. 

 The fungus penetrates the base of the outermost leaves while they are 

 still in a young condition, so the time of infection is limited and the 

 spread of the disease is slow. 



The same author || describes another species, UstilaginoideUa granii- 

 nicola, which attacks rice-plants in Guiana, and affects them like rust. 

 The hyphae are largely confined to the epidermal cells, the internal tissues 

 being entered only at an advanced stage of the disease. 



J. B. Rorer 1[ gives an account of pod-rot, canker, and chuponwilt of 

 Cacao, all of them caused by the same fungus, PhjUyphthora omnivora. 

 It can gain entrance into the pod at any age through the unbroken 

 epidermis, and growth is so rapid that the pod becomes black, dry, and 

 shrivelled within 2-4 to 48 hours. Species of Nectria have been found on 

 the diseased tissues, but they are saprophytic. Spraying is advised as a 

 check to the disease. 



Griffon and Maublanc** publish notes on several cases of disease. 

 They find that young branches of Epirea had been injured, not by 

 Cladosporium, as was at first supposed, but by an insect. Olives sent 



* C.B. Soc. Biol. Paris, Ixx. (1911) pp. 752-3. See also Bot. Centralbl., cxix. 

 (1911) p. 19. t Ann. Bot., xxvi. (1912) pp. 129-31. 



X Dap. Agric. Trinidad, ix. (1910) pp. 32-4. See also Bot. Centralbl., cxix. 



(1911) p. 23. § Ann. Bot., xxv. (1911) pp. 363-5. 

 11 Ann. Bot., xxv. (1911) pp. 364-8. 



«|f Bull. Dep. Agric. Trinidad, ix. (1910) p. 65. See also Bot. Centralbl., cxix. 



(1912) p. 52. ** Bull. Soc. Mycol. France, xxvii. (1911) pp. 469-75. 



