288 FUNGI. [dsteroma. 



seriato-confluent following tlie direction of tlie nerves, slightly 

 hairy opaque black. Fr, SysL 3Iyc. v. 2. p. 563. — h, Poten- 

 tilled reptantis ; shining collapsed rugose. Purt, MSS. — c- 

 Potentillce vernce ; shining, even. Sp. PotentillcB, Sow.! L 370. 

 /. 2. 



On living leaves of Potentillce. — b. sent by Mr. Baxter to Mr. 



Purton c. Sowerhy The slight hairiness of Fries* plant depends 



probably on the silvery down of the matrix. 



14. D. AlchemillcBy Grev. {Lady s-Mantle Dothidea) ; epi- 

 phyllous black seated on a pallid spot, perithecia slightly promi- 

 nent connate disposed in rows which radiate from a common 

 centre. Johnst. ! Ft. Berw. 2. p. 133. — Asteroma AlchemillcB, 

 Grev. Ft. Ed. p. 369. Fr. El. 2. p. 152. 



On living leaves of Lady's-mantle. Common in Scotland. — " When 

 mature consisting of black minute raised points or very short lines 

 ckistered on pale circular spots of the leaf. The points are irregularly 

 arranged, but they are most closely set in the centre and assume alto- 

 gether an obscure star-like form." Jolmst. I. c. This species again, 

 which is described as an Asteroma by Dr. Greville, appears to me 

 much more conveniently placed in Dothidea, as there is nothing like 

 the filaments of Asteroma^ though the perithecia are disposed in 

 rows. 



15. D. Robertidni, Fr. (Herb Robert Dothidea) ; epiphyllous, 

 scattered hemispherical even shining black, white within. Fr.. 

 Syst. JMyc. v. 2. p. 564. Grev. Sc. Crypt. Fl. t. 146./. 1 — 

 Cri/ptosphcBria nitida, Grev. Fl. Ed. p. 363. Baxt. ! Ox, 

 n. 78. 



On green leaves of Geranium Robertianum. Nery common. Also 

 on Geranium rotundifolium. ^^ Dothidea &'era«fi." Purt. MSS. ^ 



16. D. dltiea, Pers. (Alder leaf Dothidea) ; growing on either 

 side of the leaf scattered subrotund black shining, rugoso-plicate 

 when collapsed. Fr. Syst. Myc. v. 2. p. 564. Scler. Suec. / 

 *S'. n. 288. Grev. Sc. Crypt. Fl. t. 146./. 2.—Xyloma alneum, 

 Pers. Syn. p. 108. Moug. S)- Nest.! n. 78. Piirt. v. 3. p, 

 318. Grev. Fl. Ed. p. 368. 



On green Alder leaves. Common. — Fries remarks the great simi- 

 larity between this species and Sph. artocreas. I find the fructification 

 of that plant, when growing on Oak leaves, precisely the same as what 

 is figured by Dr. Greville in D. alnea. 



64. Asteroma. Dec. Asteroma. 



Cells very small, slightly prominent, close, subconfluent, 

 seated on more or less distinctly radiatingy?3n7/<8. — Name from 

 astrum, a star. 



1. A. reticuldtum, Dec. (reticulated Asteroma) ; epiphyllous, 

 black subseriate, the cells joined by free longitudinal creeping 

 somewhat branched fibrillee. — Dothidea reticulata^ Fr. Syst, 



