HYPODERMELLA. 



235 



apothecia were present on the upper surface of the needles as 

 isolated black spots or united into lines; they dehisce by an 

 elongated fissure. The asci are cylindrical with rounded apices, 

 and measure about 110m in length; they are almost sessile. 

 Each contained four hyaline, unicellular, club-shaped spores 



ii\ 



Fic. 119. — Hypodermella sulcigena. The 

 apothecia form black lines on the needles. 

 Ascus containing four spores (enlarged). 

 Single spore with a gelatinous covering 

 (still further enlarged). (Cop. from 

 Rostrup.) 



Fig. 120. — ffypodennella laricis. Larch- 

 needle -with apothecia on the under side. 

 Af Paraphyse, and an ascus containing 

 four spores. B, Isolated (enlarged) asco- 

 spore in its gelatinous coat. (v. Tuheuf 

 del.) 



(66 m X 16/u) with a gelatinous membrane. The paraphyses 

 are simple hyaline filaments, shorter than the asci. 



Lophodermium. 



The oblong apothecia are embedded in the host-tissues under 

 a thin black cover, which breaks by a long fissure. The club- 

 shaped asci contain thread-like unicellular spores, with a 

 mucilaginous membrane. The paraphyses are sometimes septate 

 and furnished with hooked or button-shaped ends. The spores 

 reach maturity on killed portions of plants, and are forcibly 

 ejaculated. The formation of pycnidia (spermogonia) precedes 

 that of apothecia. Many members of this genus are destructive 

 enemies of plants. 



Lophodermium pinastri (Schrad.).^ Pine-blight or needle- 

 cast. (Britain and U.S. America.) This disease of the Scots pine 

 (Pimis sylvestris) is very injurious to young plants, especially 

 those in nurseries. 



'Hartig, Diseases of Trees, Evig. edit., 1894. 

 Prantl, Flora, 1877 ; also, Forstwiss. Cenlralblatt, 1880. 



