THE AUSTRALIAN NATURALIST. 123 
as from Mueller River, Queensland, by C. W. Birch. The 
specimens very closely resemble some forms of Cladonia 
foluacea, especially the var. Convoluta, and by some Lichen- 
ologists, has been placed under this genus. A very closely 
allied species, Cladonia degenerans form eratica, has been 
found at Woodburn, Saddle Hill, New Zealand, which is 
said to become curled up into ball-like masses, detached 
from the ground in the course of time, and then roll 
freely before the wind on the downs about the seaward 
base of Saddle Hill. In the journal of botany, vol. liii. 
(1915), 308, some notes are published on still another 
interesting species of lichen, Parmelia revoluta var. con- 
centrica, which Mr. R. Paulson exhibited at the Essex 
Field Club on 28th November, 1914. In this case it is 
reported that the plants were found on the grass quite 
unattached to any substratum, and are liable to be moved 
about by the wind when it blows with any force. Some 
few years ago (vide Proceedings Linnean Society of 
N.S.W., Vol. xxxiv. (1909), 591), I drew attention to the 
rapid unfolding of the thallus of Heterodea Mielleri, as 
well as Parmeliopsis semiviridis, when the specimens were 
moistened with water, and pointed out that they were even 
more interesting than either the Hygrometric Club Moss 
(Selaginella lepidophylla) or the Syrian ‘‘Rose of Jeri- 
cho”’ (Anastatica hierochuntica), which were frequently 
offered for sale to travellers, with circulars extolling the 
virtues, real or imaginery, of these two species. Another 
species of lichen, which has attracted considerable atten- 
tion, is the so-called ‘‘ Wandering Lichen of the Desert,’ 
or “‘Manna Lichen’’ (Aspicilia esculenta (Pall.) Blenkin). 
Several extremely interesting articles on this species have 
been written, and some of the authors who have gone into 
the matter very carefully, chiefly from the biblical stand- 
point, think it likely that Aspicilia esculenta Elenkin 
(Lecanora esculenta Pall.) is the original of the manna. 
The word ‘‘manna’’ is, in Etoe’s opinion, derived from 
the Hebrew words Man = food, and hu = = pre- 
pared; the Jews are supposed to have exclaimed, ‘‘Man 
hu’’ at the sight of the rain of manna. 
An article published by A. Elenkin points out that 
a certain group of lichen separate early from the stratum 
on which they grow, and live in this state for an unlimited 
time, and may be blown about in this period enormous 
distances over the deserts and plains. In the Gardener’s 
Chronicle, 1849, p. 581 and p. 611, a very full account 
is given, in which it is pointed out that a substance, eagerly 
