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SCLERODERMA GEASTER, Fr., A New British Fungus. 



BY C. E. BROOME, ESQ., F.L.S. 



Micboli was the first to distinguish Scleroderma Geaster, Fr. , in his ' Nova 

 Genera Plantarum,' p. 219 t. 99, fig. 1, where he published it has a distinct 

 species under the name of Lycoperdastrum rotandum majus. After that it ap- 

 pears to have been passed over by botanical writers till Persoon took it up and 

 designated the genus Scleroderma, from its hard integument ; his specific name 

 for our plant, polyrhizum, seems to have been less suitable, as it applies equally 

 to others of the genus. 



Fries in his 'Systema Mycologicum, iii. 46, named the species more appro- 

 priately S. Geaster, on account of its resemblance to the plants of that genus. In 

 his monograph of the Lycopcrdacece, Vittadina remarks that the species of Sclero. 

 derma, are few, but so variable in character that they are only to be recognized 

 after a long acquaintance. The differences in the colour of their peridia, the 

 size and form of the uterus, and the presence or absence of a stem, he considers 

 of little moment, nor are those consisting in the colour of the flesh and spores 

 much more reliable, for the same species exhibits these of various tints, according 

 to differences of soil and atmosphere ; much depends on the slowness or rapidity 

 of developement, which are manifestly connected with climate and temperature. 

 He places more reliance on a careful comparison of specimens from different lo- 

 calities, and collected under various atmospheric conditions, combined with 

 careful microscopical study of fructification. The greater number of the so- 

 called species the Italian botanist refers to S. vulgare, F., S. Geaster being the 

 only other with which he is acquainted which he thinks worthy of specific rank. 

 He describes it as possesinga very thick peridium splitting at the apex in a stel- 

 late manner, with a smooth, somewhat furfuraceous cortex, of a yellowish-grey 

 colour. The flesh black or brown-purple, and the spores olive-brown. 



Vittadini desciibcs two varieties, the first is emergent, sessile, globose, or 

 transversely elongated ; flesh at first watery- white, then black, variegated with 

 white walls. The inner sabstance of the peridium, when recent, whitish-yellow ; 

 when dry, of a pale woody tint, rather corky ; in the young condition, when dry, 

 strongly plicate-rugose, with black flesh almost stony inconsistence, shining when 

 rubbed. This is frequent near Milan in oak and pine groves in autumn. The 

 second variety is developed beneath the soil, substipitate, pear-shaped, 2 — 5 

 inches across ; peridium 2 — 3 lines thick, purplish-white within, clothed with 

 scales mixed with sand, and of a permenant yellow colour, scarcely rugose when 

 dry ; flesh at first watery, white, hard, at length a dirty purple colour, soft, varie- 



