20 FAELOW ON THE GYMNOSPOEANGIA 



Sporiferous masses flattened and brownish when dry, becoming hemispherical or oval 

 and rugose when swollen, and of a light yellow color, about a quarter of an inch high ; 

 spores linear-oblong, obtuse, two to six celled, most frequently three or four celled, 

 50^-84^ long, by 16fi-20fi broad ; promycelia one or two from each cell. Mycelium per- 

 ennial, forming node-like swellings in the branches. 



On leaves and stems of Cupressus thuyoides, Newton, Dedham, Wood's Holl, Mass. 

 (Farlow) ; Newfield, N. J. (EUis). 



On Libocedrus, Yosemite, Cal. (Harkness and Moore). 



A striking species first found by Mr. EUis in New Jersey, and although only known 

 apparently in a few localities it is probably common on Cupressus thuyoides throughout 

 the Atlantic States. It often accompanies G. Ellisii for which, however, it cannot pos- 

 sibly be mistaken. As in that species the distortions produced by G. biseptatum can be 

 seen at a considerable distance. The mycelium is perennial, and is found in the leaves and 

 branches, principally in the latter. 



In the leaves the mycelium produces no perceptible distortion until the sporif- 

 erous masses appear. There is only one mass to a leaf, and it is first seen as a 

 brownish elliptical protuberance emerging from the edge of the leaf. In the stem 

 the distortions are marked and may be seen at a distance. The mycelium is found 

 principally in the region of the cambium, and oval or oblong swellings are formed 

 from one to two inches long, the bark becomes distended and cracked, and the sporiferous 

 masses are found in the fissures, at first in small pulvinate tufts which on sweUing form 

 shapeless masses of rather a light yellow. The swellings increase year by year, and at 

 length become very marked, the fungus growing constantly outwards, and producing 

 fresh crops of spores year after year. The swellings are sometimes found in the main 

 trunk of the tree, and I have seen them more than a foot in diameter. However large 

 they may become, the heart wood generally remains firm and hard, and does not become 

 spongy and riddled with holes as is the case with the branches attacked by G. Ellisii, 

 which on the whole is decidedly more injurious to the trees than G. hiseptatum. 



The spores of the present species are characterized by the great variability in the 

 number of cells of which they are composed. The most usual number is three or 

 four, two are rather common and occasionally there are as many as six. The spores are 

 rather stout and obtuse, and generally constricted at the septa. When mature and about 

 to produce the promycelia it is usual for the different cells to separate from one another 

 either wholly or in part, as is well shown in PI. 2, fig. 20. The spores of the present 

 species when fully grown are not easily mistaken for those of any other species, but the 

 young tufts on the leaves often bear spores which are all, or nearly all, two-celled. I have 

 received specimens from Mr. Ellis, with the fungus confined to the leaves, and it was difii- 

 cult to say to what species to refer it. Large sets of specimens collected at Newton, how- 

 ever, show that whUe the young spots on the leaves may have principally two-celled 

 spores, those on the smaller branches have about an equal proportion of two and three 

 celled spores, and the still older spots have a large proportion of three-celled spores. In 

 short, the variability is so great that without a large set of specimens, one would have 

 difficulty in convincing himself that the extreme forms belonged to the same species. 



