JEHANGIR FARDUNJI DASTUR. 189 



the fields or by inoculations in the laboratory such hyphse have 

 never been seen. 



Puke Culture. 

 Klebalm 1 succeeded in getting a pure culture of Ph. omnivora 

 by inoculating agar in a Petri dish, directly from an infected beech 

 seedling, but the Phytophthora on Ricinus could not be taken into 

 pure culture by this method or by the ordinary poured plate method 

 successfully employed by Rorer for getting a pure culture of Cacao 

 Phytophthora, possibly because this fungus gives only a submerged 

 growth on glucose meat-extract agar, as was found when working with 

 pure cultures. Ph. infestans 3 , Phaseoli* omnivora, var. Arecat 

 and Colocasiaf' have been taken into culture by cutting aseptic- 

 slabs from the diseased tubers, fruits and rhizomes ; a pure culture 

 of Ph. Syringes was got by Klebalm 7 by incubating the rind of a 

 diseased stem of Syringa ; evidently these methods could not be em- 

 ployed in the present case as in nature the fungus is found only on 

 stems of tender seedlings six to eight inches high and on leaves. 

 Flaming killed both the host and the parasite. Diseased leaves 

 were suspended over sterilised pieces of carrot, potato, and in moist 

 chambers on agar plates so as to allow conidia to drop on to the 

 slabs and agar plates ; this method has been used with success by 

 Rolfs 8 in getting pure cultures of Rhizoctonia from the basidiospores 

 of its Corticium stage ; with Ph. parasitica the media always got 

 contaminated with bacteria and other saprophytes. Raciborskr' 

 says he has grown Ph. Nicotiana in artificial culture but does not 

 describe his technique. 



1 Klebahn, H. Joe. cit. p. 70. 



2 Rorer, J. B. Pod-Rot, Canker and Clmpon-Wilt of Cacao caused by Phytophthora 

 Sp., Bull, of Trinidad Dept. of Agr., IX, No. 65, 1910, p. 14. 



5 Clinton, (!. P. Downy mildew or blight {P. infestans (Mont) de Bary), of Potato, II, 20th 

 Report of the Connecticut Exp. Sta. 1905, p. 278. 



* Ibid., Downy mildew or blight {P. Phaseoli Thaxt.) of Lima beans, ib., p. 278. 



6 Coleman, L. C. loc. cit., p. 69. 



* At Pusa. An account of this species by Dr. E. J. Butler and Mr. G. S. Kulkarni is in 

 the press. 



1 Klebahn, H. ioc. cit., p. 37. 



8 Rolfs, F. M. Potato Failures, Bull. 91, Colorado Expt. Sta. 1904, p. 10. 



9 Raciborski, M. Parasit. Alg. Pilze Javas, Thcil III, 1900, p. 5. 



