10 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Fungi. 

 (By A. LoRRAiN Smith, P.L.S.) 



Phytophthora parasitica sp. n.* — Jehangir Fardimgi Dastur gives 

 an account of this fungus wliicli causes a disease of seedlings and leaves 

 of Ricinus communis. Dastur has found and described the sporangia 

 and the sexual organs, but oospores have not been observed in nature. 

 He has made a series of culture and inoculation experiments, and he 

 traces the development of the fungus throughout its life-history. He 

 has also added the results of various tests as to the composition of the 

 membranes. He found that the plugs which close the cells are formed 

 of cellulose and not callose ; that the sporangia are of pure cellulose as 

 are the an'theridial walls. Various other plants — chiefly in the seedling 

 stage — were inoculated, and took the disease. 



Study of the Lower Fungi. t — B. Nemec presents the results of his 

 research on Olpidium Brassicse and two species of Entophlyctis. The 

 former occurs regularly in plants of Brassica oleracea which are already 

 attacked by Flasmodiophora. Before the Srst nuclear division the para- 

 site swells to a large size. Nuclear division seems to depend on com- 

 bined nutrition and stage of growth, and the one nucleus may increase to 

 64. The expulsion tube arises as a papilla on the side nearest the peri- 

 phery of the host, and the zoospores which have been formed from the 

 nucleate cytoplasm pass out. The author also found Olpidium fre- 

 quently in the cultures. 



In the cortical cells of the host there was lodged Entophlyctis Brassicse 

 sp. n. ; a second species E. Salicornise new to science was discovered 

 in the roots of Salicornia herbacea. The develop)ment of these fungi is 

 described. 



Life-history and Cytology of Polyphagus EuglenaB.J — This species 

 has been carefully examined by II. Wager. It has long been known as 

 a fungus in which sexuality had been distinctly proved. Reproduction 

 takes place by the production of zoospores in sporangia or by sexually 

 produced zygotes. Folypliaijus is in the vegetative condition unicellular 

 and uninucleate, and is provided with delicate pseudopodia which pene- 

 trate and distintegrate the resting cysts of Euylense. A single fungus 

 by various pseudopodia may be in contact with many Euylense. 

 Asexual sporangia are formed as an outgrowth of the vegetative cell ; 

 the zoospore is uniciliate ; a yellow oil-drop is present at the base of 

 the flagellum and in close contact with the nucleus : it has been sug- 

 gested that it may be functional in connexion with the phototaxis of the 

 zoospores. The nucleus of the vegetative cell is frequently arc-shaped 

 and in close contact with a light stainable nucleoplasm ; it is surrounded 

 by deeply staining chromidia. 



* Mem. Dep. Agric. India, v. (1913) pp. 177-231 (10 pis.). 



t Bull. Intern. Acad. Sci. Boh^me (Prague, 1912) 11 pp. (2 pis. and 1 fig.). See 

 also Bot. Centralbl, cxxii. (1913) p. 564. 



: Ann. of Bot., xxvii. (1913) pp. 173-202 (4 pis.). 



