242 AGRICULTURAL EXPERIMENT STATION. [Jan. 



the other spore forms of the fungus, and that this last 

 development cannot occur if the disseraiuivtion of cluster- 

 cup spores be prevented. That this is true has not yet 

 been proven, but, in the light of what we know of other 

 rust fungi, it may fairly be assumed until more positive 

 information is available. 



4. A Hazel Fungus {Cryptosporella anomala (Pk.) 

 Sacc.) (PI. IV.) was left at the station in April by Mr. 

 Henry Graves of Palmer. He reported it as killing the 

 canes of the European hazel {Corylus avellana) in a planta- 

 tion owned by him, and as attacking an annually increasing 

 portion of the plantation. The fungus proved to be that 

 known by the above name, which was first described by 

 Peck,* who observed it on the same host at Albany, N. Y., 

 as Diatrype anomala. It appears in the form of protuber- 

 ances with elliptical bases (fig. 30) that burst the bark and 

 arise rather thickly from the affected portion of the branch 

 (a, fig. 30), which is sunk below the surface of the healthy 

 part. A transverse section of the l)ranch passing through 

 one of these protuberances shows well the structure of the 

 fungus and its relation to the host-plant. The interior of 

 the protuberance, which is the fructificative part of the 

 fungus, is seen to contain numerous ])lack, flask-like struct- 

 ures, whose tips reach the surface of the protuberance (fig. 

 31). Within the cavities of these flasks are formed the 

 very numerous spindle-shaped spore sacs (fig, 32), each 

 containing, when ripe, eight colorless, elliptical spores. It 

 is very noticeable that, in the part of the branch occupied 

 by the fungus, the inner bark, elsewhere a distinct band 

 of tissue, is shrunken to a narrow black line between the 

 wood and outer bark (a, fig. 31). This reduction in the 

 thickness of the inner bark explains at once why the surface 

 of the affected parts is sunken below the rest of the surf;ice, 

 and shows that the chief seat of the vegetative activity of 

 the fungus is in the rich growing and conducting tissues of 

 this part of the branch. The destruction of these tissues 

 must, in any event, have serious consequences for the plant ; 

 and, if the entire circumference of a cane becomes involved, 



* Twentj'-eiijhth Report New York State Museum, p. ~1, 1870. 



