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Page number:144 
Remarks (internal):The other species, C. lactucae Henn. on lettuce has colored conidia. Fragoso has described a C. longissima var. gigantea on Tamus cominunis Linn. It, however, is not related to the lettuce species and apparently is identical with C. scandens. Cooke and Ellis (Grevillea 17: 65. 1889) list a Cercospora longissima on beet, but add it is a synonym of C. beticola. Peck described a Cercospora longispora on Lupinus in 1881, and it is for this reason that Saccardo changed the name of the lettuce fungus. Sawada merely renames the fungus Welles had described. His description of the form on L, indica fits accurately the common one on lettuce. The same is true for the one on Ixeris chinensis. Toro (Phytopath. 19: 973. 1929) already has shown that the Welles and Stevenson names are synonyms of C. longissima and that C. lactucae P. Hennings is distinct. McWhorter (Phytopath. 15: 247. 1925) points out the similarity of the Welles and Stevenson fungi. Still other authors have mentioned the same or related facts.
Description type:Non-original description 
Description:Cercospora longissima (Cugini in Herb.) Saccardo
Syll. Fung. 18: 607. 1906
Cercospora longispora (Cugini in Herb.) Traverso, Malpighia 17: 217. 1902
Cercospora lactucae Stevenson, Jour. Dept. Agr. Puerto Rico 1: 105. 1917
Cercospora lactucae Welles, Phytopath. 13: 289. 1923
Cercospora lactucae-sativae Sawada, Formosa Agr. Res. Inst. Rept. 35: 111. 1928
Cercospora ixeridis-chinensis Sawada, Formosa Agr. Res. Inst. Rept. 86: 171. 1943
Cercospora lactucae-indicae Sawada, Formosa Agr. Res. Inst. Rcpt. 86: 172. 1943
Leaf spots at first minute water-soaked specks, gradually enlarging and turning various shades of tan or brown, and in some instances even dingy gray, circular to irregular in shape, 2-10 mm. in diameter; fruiting amphigenous; stromata almost lacking or only a few brown cells; most fascicles less than ten stalks; conidiophores pale olivaceous brown, slightly paler and more narrow toward the tip, multiseptate, sparingly, geniculate, not branched, medium spore scar at rounded to subtruncate tip, 4-6 x 25-80 µm, rarely as long as 200 µm; conidia hyaline, acicular to obclavate, straight to variously curved, indistinctly multiseptate, truncate to subtruncate base, subacute tip, 3-5 x 20-l00 µm, rarely as large as 6 x 200 µm.
HOSTS: Lactuca chinensis Makino (Ixeris chinensis Naka.), L. indica L., L. integri f olia Bigel, L. paradoxa, L. sativa L., L. scariola L.
TYPES: Vaciglio, Modena, Northern Italy; Lactuca sativa; Cugini; August, 1891; (C. lactucae Stev.) Rio Piedras, Puerto Rico; Lactuca sativa; J. A. Stevenson, No. 6774 and 5613; Oct. 22, 1914, and 1916; (C. lactucae Welles) College of Agr., Los Banos, Philippines; Lactuca sativa; C. G. Welles. The Sawada types of C. lactucae-indicae and C. ixeridis-chinensis are not known. He changes the Welles name to C. lactucae-sativae.
DISTRIBUTION: Studied material from New Jersey, Wisconsin, Puerto Rico, San Domingo, Guatemala, Trinidad, Uganda, Venezuela, Brazil, Colombia, China, Formosa, and the Philippines. Also reported from Japan, Florida, Illinois, Indiana, Texas, Virginia, and Louisiana. Probably occurs in all tropical and subtropical countries.
Taxon name: