34 



paler than the branches, or whitish, buff or slightly flesh-color, 

 mostly smaller than 5 mm. diameter. 



The several subspecies or varieties into which Ramalina 

 calicaris has been divided may be noted if desired. R. fcrinacea 

 (L.) is dotted over with white specks (soredia) which are never 

 large, as in R. pollinaria, while the non-inflated stalks dis- 

 tinguish it from R. dilacerata. R. canaliculata (E. Fries) has the 

 stalks distinctly channeled, and the fruits apparently on the 

 tips, but actually on the sides of branchlets which are bent 

 backward, an arrangement not confined to this form. R. jastig- 

 iata (Pers.) is a similar densely tufted form with more or less 

 rounded stalks, and fruits usually along the branches. R. sub- 

 ampUcata (Nyl.) has flattened and almost leaf-like stalks, with 

 fruits along the surface and the margins. It suggests Group 4, 

 but both sides of the stalk have the same structure and appear- 

 ance, while in Group 4 the two sides tend to differ. 



The microscope quickly distinguishes Ramalina, because 

 spores have two cells with a simple dividing wall, not thickened 

 as in Teloschistes. Size 9 to 18 by 4 to 7 microns, often with 

 tapered ends and somewhat curved at times. No other stalked 

 lichen growing on trees has spores of this kind. 



A form with much longer spores, 18 to 32 by 3 to 6 microns, 

 is distinguished as Ramalina stenospora Mueller, Narrow- 

 Spore Twig Lichen. It is not common, and not otherwise differ- 

 ent from R. calicaris. 



Ramalina froxinea (L.), Ash Twig Lichen, was listed by 

 Tuckerman as a subspecies of R. calicaris, and resembles R. 

 suhamplicata, with broad, leaf-like stalks, but the branches 

 sometimes spraying into rounded, much divided tips. The fruits 

 become much larger, often more than 1 cm. in diameter. These 

 characters are so easily seen that R. fraxinea may usefully be 

 called a distinct species. Its spores are like R. calicaris. 



The smaller Ramalina pollinaria (Ach.), Powdery Lichen, 

 usually but 1 to 2 cm. high, will sometimes be found in the 

 crevices of cliffs, or rarely on trees. I have seen it only near 

 Shoshola Falls, Penn., but it is reported from southern New 

 England. Its stalks are slightly swollen, not much branched. 

 It may be identified by the specks and relatively large, powdery 

 patches of soredia, as much as 2 mm. across, spreading over 

 its surface, and bursting from the tips. The soredia are much 



