34 



Guide to the Lichens of the New York Area — Part 6 



G. G. Nearing 



Group 7 — continued 



Solorina saccata. Dimpled Lichen 



This northern lichen is rare in the New York area, but has been 

 found growing on the ground in the Helderbergs, near Albany. It 

 looks like a brown Sticta or Peltigera, into which someone has 

 pressed the round end of a bullet here and there, then colored the 

 smooth, cup-like depressions reddish brown. These peculiar sunken 

 fruits are unlike any other lichen, except the smaller Heppia 

 Despreauxli (Group 13), and as the species is usually fertile, no 

 further description is needed to determine it. Sometimes the Hchen 

 is reduced to a mere rim 2 or 3 mm. wide around its sunken fruits. 



Peltigera. Leather Lichens having the downy under surface 

 marked by thickened, often darkened veins. The fruits form on the 

 upper surface of special lobes which project from the tips. Spores 

 are brownish until mature, when they become colorless. 



Peltigera canina. Dog Lichen 



Found everywhere growing on the ground or over mosses on 

 tree-roots and rocks. It reaches best development in the dense shade 

 of damp woods, or on stream-banks, but may also be seen in dry, 

 open places, exposed to full sun. It spreads in regular or irregular 

 rosettes as much as 50 cm. or more across, with branches and tips 

 sometimes 4 cm. wide. The tips often rise 2 or 3 cm. clear of the 

 foothold. The upper surface is leather-brown or gray, greenish 

 when moist, blackish in winter, rather smooth, but with small hairs 

 scattered inconspicuously. Or the margins and other parts may be 

 covered with tiny lobes and coral-like growths, or with soredia (in 

 the subspecies). The under surface is downy, white to brown, more 

 or less covered with a network of thickened, white, brown or black- 

 ening veins. From these veins spring similarly colored, cottony 

 holdfasts, often 1 cm. long and frequently much thickened and 

 branched. Algal cells said to be Nostoc or Gloeocapsa. but difificult 

 to determine. 



