15 



Sticta qiiercisans. Oak Leather Lichen 



A southern lichen found rarely throughout the New York area 

 on trees. It may spread as large as 15 cm., with lobes up to 1 cm. 

 across, overlapping shingle-fashion. The margins are raised and 

 crinkled, bordered with gray granules and coral-like growths. The 

 upper surface is smooth, leather-brown, often becoming reddish 

 when long dry, the under surface covered with a downy nap, and 

 speckled with cup-shaped dots 0.5 mm. or less in diameter. Algal 

 cells Nostoc. 



Fruits, rare in this region, resemble 5". sylvatica. 



For comparisons, see S. sylvatica. 



Sticta fuliginosa. Sooty Leather Lichen 



To be looked for on trees and rocks rarely throughout the 

 New York area, but less rare in New England. A small lichen, 

 usually less than 4 cm. across, but little divided, and with shallowly 

 separated lobes as much as 2 cm. across. The upper surface is 

 smoky brown, dotted or incrusted with blackish granules, the 

 under pale brown with a downy nap, speckled with whitish, cup- 

 shaped dots 0.5 mm. or less in diameter. The algal cells are Nostoc. 



Fruits rare, resembling S. sylvatica. 



For comparisons, see 6". sylvatica. 



Sticta crocata. Gold-Edge Lichen 



On trees and rocks anywhere in the New York area, rare, but 

 so conspicuous that many specimens have been collected. Grows 

 in irregular rosettes as much as 15 cm. across, branches usually 

 about 1 cm. wide, the margins lifted and crinkled, dusted with 

 bright yellow soredia, which may also be scattered over the leather- 

 brown upper surface. The under surface is covered with a brown,, 

 downy nap speckled with dusty yellow dots sometimes 1 mm. in 

 diameter. Algal cells Nostoc. 



Fruits rare in the New York area. 

 Sticta crocata and the similar .9. aurata are the only local lichens 

 speckled with yellow beneath. Cetraria pinastri and forms of 

 C. juniperina have yellow margins, but their under surface is 

 uniformly yellow and not downy. C. Oakesiana (Group 5) has 

 green or yellow-green margins, and a habit similar to Sticta cro- 



