4i8 



INTRODUCTION TO PLANT GEOGRAPHY [CHAP. 



Andreaea. The most luxuriant vegetation is often found in areas that 

 are manured (but not much trampled) by Penguins, etc. Lichens 

 inhabit the rocks, and include species of Caloplaca that introduce 

 bright colours much as in the Arctic, while Mosses may form an 

 almost continuous investment very locally (Fig. 140). But in general 

 the vegetation even around the periphery of the Continent is sparse 

 and only encountered in occasional favoured areas, most tracts 

 being ice-covered and devoid of evident plant growth, though the 



Fig. 140. — Luxuriant growth of Mosses, broken chietiy by rocks bearing Lichens, 

 extending up snow-melt gully in area frequented by Penguins, Deception Island, 

 Antarctica. Rarely is more luxuriant vegetation to be seen on or near the Antarctic 

 Continent. Note the small tussocks formed by the chief Moss, and the more 

 typical barrenness of the ground behind. (Phot. I. M. Lamb, courtesy of Falkland 

 Islands Scientific Bureau.) 



surface snow when tested has usually proved to contain some viable 

 Bacteria and often also spores of Moulds and Yeasts which had 

 presumably been carried thither by air currents. 



Further south, in the perpetually frozen zone, only a few sheer 

 walls of rock or peaks or other situations that become bare of snow 

 in the brief ' summer ' carry a sparse vegetation consisting entirely 

 of hardy cryptogams. However, some Mosses and Algae and fairly 

 numerous Lichens persist to at least 78° S., sometimes practically 

 covering suitable manured areas near the coastal shelf-ice in deep 



