250 



Mycologia 



limited to the Japanese welsh onion (Allium fistulosum) ; the 

 only plant susceptible to the disease in inoculation tests was 

 Epiphyllum truncatum (Cactaceae) . The disease is not at 

 present widely distributed and the injury not very serious. It is 

 desirable to eradicate it before it spreads to other localities. 



The paper gives a review of the genus Phytophthora and allied 

 genera; the following species are discussed: 



Phytophthora cactorum (C. et L.) Schroet., P. cactorum (C. 

 et L.) Schroet. var. Arecae Colem, P. colocasiae Rac, P. faberi 

 Maubl, P. infestans (Mont.) de Bary, P. nicotianae Breda de 

 Haan, P. parasitica Dast, P. Phaseoli Thaxt., P. Syringae Kleb.. 

 P. Thalictri Wils. et Davis, Kawakamia Cyperi (Miy. et Ideta) 

 Miyabe, Pythiacystis citrophthora Smith. 



Phytophthora Melongenae K. Sawada sp. nov. in Noji Shi- 

 ken jo Tokubetsu Hokoku (Special Report Agric. Exper. Sta- 

 tion), Taiwan (Formosa) No. u, p. 77-79, pi. 3- T. 4, iii, 

 Mar. 1915. 



Hyphae intercellular in the host tissue or freely penetrating 

 the cell wall, much branched, not septate in juvenile stage, but 

 septate when mature ; aerial hyphae mostly not branching, usually 

 attaining a considerable length, nearly uniform in diameter, the 

 base always irregularly twisted, swelled or short-branched, and 

 very characteristic; diam. of hyphae 4-8/1.; haustoria none. 

 Conidiophores hardly distinguishable from aerial hyphae, filiform, 

 delicate, very much elongated, the shortest measuring 80 ^ in 

 length, 3-5 n across ; conidia spherical, broad-oval or oval, 24- 

 72 X 20-48 ft, average 42.4 X 33-9 with apical hemispherical 

 papillae 3-5 fx high, producing several to 40 zoospores ; zoospores 

 ovoid or ellipsoid, 10-11 X8fi, with 2 cilia; chlamydospores 

 yellowish-brown, spherical, 25-42 fx in diam. ; oogonia f ormed in 

 cultures on bean agar-agar medium, spherical, 18-23 X 20-24. fi, 

 containing one oospore ; oospore spherical, walls 2 li thick, color- 

 less to very pale yellowish-brown, diameter 17-21 /x. Antheridia 

 not formed on the same hyphae that bear the oogonia but on the 

 end of other hyphae, surrounding tightly the oogonial stalk and 

 attached to the wall of oogonia at the juncture with the stalk, 

 oblate spheroidal or nearly spherical, 10-14 X 12-16 [x. 



Parasitic on the fruit of Solarium Melongena (Egg plant). 

 Type locality: Taihoku-cho, Chonaiho-sho, Taiwan (Formosa), 

 June 18, 1914, July 10, 1914, and Sept. 6, 1914. 



