2G4 THE VOYAGE OF H.M.S. CHALLENGER. 



LICHENES. 1 



Collema (Dichodiurn) byrsinum, Acharius. 



Collema (Dichodium) byrsinum, Acharius; Nyl., Synopsis Metb. Licli., i. p. 113; Crombie in Journ. 

 Linn. Soc. Lond., xvi. p. 226. 



Admiralty Islands. — On trees ; well fruited. Spread almost all over the tropics, 

 especially in maritime districts. 



Ramalina subfraxinea, Nyl. 



Ramalina subfraxinea, Nyl., Eecog. Monogr. Ramal., p. 41 ; Crombie in Journ. Linn. Soc. Lond., 

 xvi. p. 226. 



Admiralty Islands. — On branches; fertile. (Spores 0-015-0-018 millim. long, 

 0"004-0"005 millim. thick.) Ny lander records this species from New Grenada, Mauritius, 

 Bourbon, and the Marianne Islands, but he adds that it is perhaps not specifically different 

 from the very widely dispersed Ramalina fraxinca. 



Pyxine sp. 1 Crombie. 



Pyxina sp. 1 Crombie in Journ. Linn. Soc. Lond., xvi. p. 22G. 



Admiralty Islands. — On bark ; sterile and indeterminable. 



Lecanora granifera, var. leucotropa, Nyl. 



Lecannra granifera, var. leucotropa, Nyl., Licli. Antill. Husn., p. 11 ; Crombie in Journ. Linn. Soc. 

 Lond., xvi. p. 226. 



(Thallus K +, yellow; spores, 0-014-0-016 millim. long, 0-007-0-010 millim. 

 thick.) 



Admiralty Islands. — On the bark of trees ; a small specimen. 



Opegrapha subvulgata, Nyl. 



Opegrapha subvulgata, Nyl. in Flora, 1869, p. 71 ; Crombie in Journ. Linn. Soc. Lond., xvi. p. 226, 

 forma ahsita. 



DifTert apotheciis interdum csesio suffusis, sporis nonniliil turgid ioribus (longit. 

 0-023-0-032 millim., crassit. - 006 millim., 7-septatulis). Thallus variat maculiformis 

 pallescens aut fuscescens. Spermogonia non visa. 



Admiralty Islands. — On branches, apparently frequent. 



Allied to Opegrapha vulgata, Acharius, a common British species widely diffused in 

 other parts of the world. 



Extracted from the Journ. Linn. Soc. Lond., vol. xvi., 1878, with additional references and remarks on 

 the distribution of the species. 



