HYSTEROGRAPHIUM. 



233 



Eostrup ^ regards it as a parasite on Fraxinus. Twigs of the 

 ash attacked show flat collapsed plates of bark, on which are 

 developed pycnidia containing one-celled conidia, and, later, 

 the apothecia. On young twigs the diseased part often extends 

 round the whole circumference, and causes the death of the 

 upper living part. As yet I have only found this fungus as 

 a saprophyte. 



HYPODERMIEAE. 



Hypoderma. 



The apothecia are oblong, and at first closed by a thin black 

 cover, which opens by a long fissure. The asci are sessile in 



Fig. 116. — H7/poderma strobicota on Pinus 

 Strobus. Ascus containing eight ascospores 

 ■with gelatinous coats ; paraphyses with 

 clavate ends. (After v. Tubeuf.) 



Fig. 117. — Hypoderma strobicoia. Isolated 

 ascospores : with and without a gelatinous 

 coat, and one- or two-celled. (After v. 

 Tubeuf.) 



some species, but have a delicate stalk in others. The spores, 

 eight in each ascus, are never long and thread-like, but always 

 much shorter than the asci, and two-celled when mature. The 

 parapbyses have button-shaped or hooked ends. 



Hypoderma strobicola^ (Rostr.). Needle-blight of the Wey- 



iRostrup, Fortsatte Undersoegelser ov. SnyltesvampeH Angreb paa Skov- 

 traeeme, 1883. 



2Rostrup, Fortsatte Undersoegelser, 1883. 

 V. Tubeuf, Seit. z. Kenntniss d. Baumkrankheiten, 1888 ; also Botan. 

 Centralblatt, XLi,, 1890. 



Note .- When I decided to place Lophodermium brachysporum under the 

 genus Hypoderma, there already existed a Hypoderma brachysporum Speg. 

 (1887). For the future I shall therefore call Loph. brachysporum Kostr. as 

 Hypoderma strobicola. 



