410 FUNGUS-FLORA. 



Helminthosporium dendroideum, B. & Br., Ann. Nat. Hist., n. 

 946, t. xvi. f. 14; Sacc., SylL, iv. n. 1983. 

 On branches of Acer. 



Helminthosporium densum. Sacc. & Eoum. 



Shortly velvety, dense, blackish-brown ; conidia fusoid, 

 somewhat acute at both ends, straight or often vaguely 

 curved, 45-60 X 7-8 /*, 7-8-septate, not constricted, sooty ; 

 hyphae cylindrical, somewhat attenuated below, 20-40 X 

 45 5 /z, more or less septate and constricted, olivaceous. 



Helminthosporium densum, Sacc. & Eoum., Eev. Myc., 1881, 

 p. 29 ; Sacc., SylL, iv. n. 1985. 



On Morns alba. 



Helminthosporium obclavatum. Sacc. 



Effused, forming black spots ; hyphae erect, filiform, base 

 slightly swollen, 60-70 X 6-7 /x, sparingly septate, smoke- 

 brown; conidia solitary at the apex, obclavate-fusoid, be- 

 coming considerably attenuated above, 90 X 15 p., apex 

 rounded, base truncate, 18-24-septate, brownish-black. 



Helminthosporium obclavatum, Sacc., Mich., i. p. 85 ; Sacc., 

 Syll., iv. n. 1989. 



On rotten alder wood, &c. 



Helminthosporium Smithii. B. & Br. 



Forming broadly effused coarsely velvety patches on wood, 

 or sometimes forming lines, or erumpent and forming reticu- 

 lated patches on bark, black ; hyphae unbranched, flexuous, 

 septate ; conidia apical, very long, multi-septate, straight or 

 wavy, olive brown, cells cuboid, epispore very thick, 80-150 

 X 8-12 p. 



Helminthosporium Smithii, B. & Br., Ann. Nat. Hist., n. 507, 

 t. v. f. 5 ; Sacc., Syll., iv. 1991. 



On dead branches of holly, &c. 



Helminthosporium fusisporum. Berk. 



Hyphae densely aggregated, sparingly branched, obtuse, 

 blackish; conidia fusoid, 6-7-septate, narrower than the 

 hyphae. 



Helminthosporium fusisporum, Berk., Eng-. Fl., v., p. 336 ; 

 Sacc., SylL, iv. n. 2000. 



On rotten wood and branches. 



