14 FARLOW ON THE GYMNOSPORANGIA 



Podisoma macrojnis Schw., Sjn. Fung. Am. Boi\, p. 307, No. 309G, 1831 ; London 

 Jour. Bot., Vol. IV, PI. 12, fig. 6 ; Sprague's Contributions to New England Mycology,^ 

 p. 329; Curtis's Plants of North Carolina, p. 121; Peck's 23d Report, p. 57; Notes on 

 Podisoma, PI. xix, fig. 3 ; Grevillea, Vol. 3, p. 56. Exsrcc. Ravenel, Fung. Car., Fasc. 

 I, No. 85; Tliiimen,^ Mycoth. Univers., No. 148. 



Sporiferous masses aggregated in globose tufts, surrounded at the base by a rmg formed 

 by the raised epidermis and subepidermal tissue of the host-plant, orange-yellow, cylindri- 

 cal, acuminate, half an inch to an inch long or, at times, longer ; spores ovate-acute, two- 

 celled, generally constricted at the septum and with a papilla at the apex, lbu-20fj. broad 

 by 45u-60/i long ; promj^celia generally four from each cell. Mycelium annual, producing 

 globose or reniform knots in the smaller branches. 



On leaves and smaller branches of Junlperus vlrrjhi'iana. 



Common from Massachusetts to South Carolina (Ravenel, Mellichamps), and extending 

 west to Missouri (Englemann), Colorado (Palmer), and Wisconsin (Lapham). 



The common "cedar apple" of the Atlantic States, and the most striking species of 

 the genus. It is very abundant .along the seaboard, but becomes rarer in the west. The 

 knots together with the sporiferous masses, often measure three inches across when swollen. 

 When dry the sporiferous masses are much shrunken, and as the knots do not differ much 

 in color from the branches, they are not well seen from a distance. The species was first 

 described by Schweinitz, in 1822, under the name of G. Juniperi virginianae. Link in 

 1825, described it in the Species Plantarum (Linnaeus and Willdenow), under the name of 

 G. inacrojms, but why the Schweinitzian name was sujjpressed, or why Link placed the 

 species in Gymnosporangium rather than Podisoma, a genus of his own creation, is not 

 clear. In 1831, in the Syn. Fung. Am. Bor., Schweinitz adopted Link's specific name, but 

 placed the species in Podisoma, and it has generally been known since as Podisoma 

 raacropus Schw. Fries, however, retained Schweinitz's original specific name, and called 

 our plant Podisoma JunijJeri virginianae. Notwithstanding that Schweinitz's name given 

 in the Syn. Fung. Carol. Sup., is the oldest, it must be abandoned in consequence of the 

 confusion and awkwardness which has arisen from applying the compound names Juniperi 

 virginianae, Junij^eri communis, Juniperi Sablnae, etc., to denote the different species. 

 The present species, moreover, is by no means the only one found on J. vlrgmiana, and 

 it is on all accounts desirable to retain the name given by Link, and afterwards adopted by 

 Schweinitz himself, at least as far as the specific name is concerned. 



The mycelium of G. macroims is abundant, and easily seen. It is found principally in 

 the leaves, and there are haustoria which enter the parenchymatous cells. The fungus 

 causes the leaves to swell, and finally ruptures them at about the central portion. One 

 then sees a rounded mass tipped with the comparatively unchanged apex of the leaf In 

 some cases the gelatinous columns are produced when the knot is quite small, so that not 



iProc. Boston Soc. Nal. Hist., Vol. v. 1856. sisted in sending a letter with a drawing of the fungus to 



2 Streinz, Nomenclator Fungorum, p. 455, gives Wyraan Berkeley, asking the name of the species. The letter and 



as the authority for the species and in this error he is fol- Berkeley's reply that the fungus was Podisoma macropus 



lowed by Von Thiimen. The Wyman in question was Prof. Schw. were published in London Jour. Bot., loc. cit. 

 Jeffries Wyman, whose only connection with the species con- 



