OF THE UNITED STATES. 19 



base and taper upwards, but are comparatively broad and flattened even at tlie apex. 

 The scars left by the sporiferous masses of the previous year are distinctly visible between 

 the bases of the newly formed masses. The knots seldom attain a great size and rarely 

 exceed an inch in diameter. They usually appear to be terminal on the smaller branches, 

 but sometimes they form nodes in the continuity of the branches.. In course of tiiue the 

 surface of the knots becomes grayish and irregular by the action of the weather, but they 

 are always more compact and harder than the knots of G. macropus. The leaves are not 

 usually distorted by the fmigus, but when the knots are large, the leaves on the upper 

 branches above the knots become somewhat hypertrophied . 



What we have called variety globosum, is certainly common in the Eastern States. It 

 often accompanies G. macropus, and is in Eastern Massachusetts about as common as that 

 species, and Mr. Peck states that it is still more common in the region of Albany. How 

 far west the variety extends is unknown. The southern limit, as fiir as I can ascertain, is 

 Bluffton, S. C, where it was collected by Dr. Mellichamp. Although often accompanying 

 G. macropus, and like it producing what are popularly called " cedar apples," there is no 

 doul^t that the present form is distinct fi'om it as is shown by the fact that it is perennial 

 and not annual, and by the very different character of the knots formed, and the appear- 

 ance of the sporiferous masses. A very slight experience will enable any one to distin- 

 guish between the two at sight. The only question which can arise is whether the fungus 

 in question is distinct from G.fuscum, and on this point it is not so easy to give a decided 

 an.swer. The variety, if indeed it be not a distinct species, differs entirely from the type 

 in the character of the distortions produced on the same host-plant, ./. vlrglnlana, and it 

 may be said with considerable truth that the same species of fungus could not produce 

 two such different distortions in the branches of the same species of plant. The sporif- 

 erous masses, however, are in shape and color much like those of G.fuscum, and 

 the spores themselves, the size and shape of which, at the best, are variable even in the 

 same species, although in general smaller than in G. fuscum, are not sufi&ciently distinct 

 to allow one on the strength of their smaller size alone, to separate the fungus as a dis- 

 tinct species. The question is, does not the smaller size of the spores in connection with 

 the peculiar distortions caused by the fungus warrant one in regarding it as different from 

 G.fuscuml I think it quite possible that the two are distinct, but am unwilling to speak 

 positively without more information with regard to the mode of occurrence of G. fuscum 

 on J. virginiana in Europe. So far as I know, however, the globose distortions are 

 unknoAvn in Europe, the only case known to me where a globose mass is figured, being in 

 Cooke's notes on Podisoma, PL 19, fig. 2, but it is not there stated whether the figure 

 was drawn from a European or an American specimen. 



Gtmnospoeangium biseptatum Ellis. 

 PI. 2, figs. 18-21. 



Gymnosporangium biseptatum Ellis, in Bulletin of Torrey Club, Vol. v, p. 46, 1874; Far- 

 low in Bull. Bussey Inst., Vol. ii, p. 220 ; Vize in Grevillea, Vol. vii, p. 11; Harkness 

 and Moore, Catalogue of the Pacific Coast Fungi, p. 25. Exsicc. Ellis, North American 

 Fungi, Fasc. iii, No. 272. 



