282 PAULSON I NOTES ON THE ECOLOGY OF LICHENS. 
Thompson 5 . During the autumn of 1917, there was a remarkable 
growth of Lecidea uliginosa Ach. on heaths and commons around 
London, upon soil that had been worn bare during the previous 
summer through various causes. It appeared as a dark, almost 
black, stain upon the ground. Patches as long as 8ft. by 6ft. 
were measured at the cryptogamic meeting of the Essex Field 
Club, on 10th November last, on the open ground in front of 
the King’s Oak Hotel, High Beach. The abundance of fertile 
Bceomyces roseus Pers. near Oak Hill was seen at the same 
meeting. It has not been fertile there for at least twelve years. 
LICHEN FLORA OF FIVE HEATHLANDS NExAR LONDON. 
Heathland.— Calluna vulgaris or Erica tetralix dominant. 
Species of Lichen. 
Heath near 
- 1 Sevenoaks, 
Kent. 
Jacks Hill 
Heath, 
Epping 
Forest. 
Oxshott 
w Heath, 
Surrey. 
Oxshott 
Heath, 
Surrey. 
Woodreddon 
Hill, 
Epping 
Forest. 
Cl ado ni a sylvatica Nyl. 
Dry 
Heath. 
X c. 
Dry 
Heath. 
Drv 
Heath. 
X ab. 
Wet 
Heath 
1 f.c. 
Wet 
Heath 
X f.c. 
,, f.mbriata Er. 
— — 
— — 
X f.c. 
— — 
X r. 
,, furcata Hoffm. 
X C. 
X f.C. 
X c. 
X f.c. 
X f.c. 
,, coccifera Schoer. 
X r. 
X r. 
X r.r. 
— — 
- - 
,, macilenta Hoffm 
X ab. 
X ab. 
X f.c. 
X f.c. 
- - 
,, Flcerkiana Fr. 
X c. 
X r.r. 
X ab. 
X C. 
X r.r. 
Bceomyces rufus D.C. 
X v.r. 
X v.r. 
— — 
— — 
— — 
,, roseus Pers. 
X v.r. 
X v.r. 
- —— 
- - 
-- 
Cetraria aculeata Fr. 
X f.c. 
- - 
X ab. 
-- -- 
- - 
Peltigera spuria Leight. 
— — 
X r. 
- - 
- - 
X r. 
Lecidea granulosa Schoer. 
X v.c. 
X ab. 
X ab. 
X v.c. 
-- 
,, uliginosa Ach. 
X c. 
X ab. 
X ab. 
X v.c. 
X f.c. 
Nature of Soil. 
1. Lower Greensand. 
2. Sandy Gravel. 
3. Bagshot Sands. 
4. Bagshot Sands, with Pan. 
5. Sandy Gravel (as No. 2.) 
Abundance or Scarcity. 
ab.=abundant. v.r.=very rare. 
v.c.=very common. r.r =rather rare-, 
f.c.—fairly common. r. = rare. 
c.=common, 
When considering the rate of growth of lichens, it is very 
necessary to distinguish between those with a thallus of very 
loosely-woven threads and those with a well-developed foliose 
thallus. The two just described have the former texture. Hav¬ 
ing asked a correspondent, a well known Hellenist of Yorkshire, 
5 Essex Naturalist, vol. xviii., p. 39 (1915). 
