186 



LICHESTACEI. 



[RAMALINA. 



Tribe IX. RAMALINEI Nyl. Bull. Soc. Linn. Normand. 

 ser. 2, iv. (1870) p. 103. 



Thallus fruticulose, laciniose, or filamentose, rounded or com- 

 pressed, erect or pendulous, internally with woolly arachnoid me- 

 dulla. Apothecia lecanorine, scutellate, terminal or lateral ; spores 

 8na3, 1-septate, suboblong, straight or slightly curved, colourless ; 

 paraphyses discrete. Spermogones immersed or slightly prominent ; 

 sterigmata subsimple or pauci-articulate, with long anastomosing 

 filaments intermixed. 



This tribe, under which Nylander in his former arrangement included 

 Alecioria and Evernia, is now, in its more limited acceptation, regarded 

 by him as quite distinct, on account of marked analytical differences, 

 more especially of the thalamium, while the structure of the spermogones 

 is entirely peculiar (vide Ramal. Monogr. I. c.). The exotic genus Ramalea 

 Nyl. externally resembling JRamalina, ought, from the type of the sper- 

 matia, to be relegated to the Cladoniei ; while Dactylina and Dufourea, 

 neither of which occur in Britain, are also excluded f ro.u this tribe. 



36. RAMALINA 



Ach.Lich.Univ.(1810) 

 p. 122. Thallus cses- 

 pitoso-fruticulose, foli- 

 aceo - complanate or 

 rounded, somewhat 

 shining or subopaque, 

 soft or rigid, solid or 

 fistulose, ramoso-lacini- 

 ate.concolorous on both 

 sides ; medullary layer 

 arachnoid, becoming 

 sometimes very lax, cor- 

 tical layer composed 

 either of indistinct cells 

 or of longitudinal con- 

 glutinate filaments. 

 Apothecia scattered, 

 opaque, subconcolorous 

 with thallus ; hypothe- 

 cium colourless ; spores 

 small ; paraphyses thin 

 or moderate, thicker or 

 clavate at the apices ; 

 hymenial gelatine blu- 

 ish, then violet with 

 iodine. Spermogones scattered ; spermatia straight, cylindrical, or 

 oblongo-cylindrical. 



The species of this genus, formerly little understood, have recently had 

 new light thrown upon them by the minute researches of Nylander. He 



Fig. 39. 



Ramalina fraxinea Ach. a. Longitudinal section 

 of (one side of) thallus, x2UO. b. Theca and 

 paraphysis, X350. c. Spores, X500. d. Sec- 

 tions of two spermogones, X30. e. Sterigmata 

 and spermatia, X 500. (Also on the left a 

 fragment of the anastomosing spermogouic fila- 

 ments.) 



