FROM THE FALKLAND ISLANDS. 157 
These figures show that the floras of the two regions have somewhat in 
common, and the affinity is largely amongst the fruticulose forms. 
In a general way the wide distributional range of lichens must he 
attributed to the general dispersal of their spores by wind and to their hardy 
nature, their power of enduring cold and desiccation being well known to 
be remarkable (cf. Fungi, р. 158). Why it is that widespread and cosmo- 
politan species are much more numerous amongst fruticulose forms is 
not at all clear. Darbishire remarks with regard to this point :— The 
frutieulose species are the oldest and probably least variable at present. 
The erustaceous species are more variable and have adapted themselves more 
to local conditions, thus giving rise to new species” (12, p. 63). The human 
factor also is no doubt, as Darbishire allows, partly responsible, the minute 
size of many crustaceous plants making them easily overlooked and more 
difficult to identify from any book-descriptions. 
The Kerguelen flora, which was not touched upon by Darbishire, shows on 
comparison two interesting features. In the first place, the scarcity of 
fraticulose and foliaceous plants is very noticeable. In Zahlbruckner's list, 
which is the most recent and, exeluding Crombie's papers, the only one 
critical, this is exceedingly marked, only 1 Cladonia, 1 Sticta, 1 Parmelia, 
and 2 Usneas out of a total of 43 being recorded. Hooker and Taylor 
enumerated a few other large species, as did Crombie, but there is some doubt 
as to the earlier records (vide Crombie, '76, p. 180). The bleakness and 
barrenness of Kerguelen is well known, but with so many fructiculose and 
bulky foliaceous species in Ше Falklands (amongst others, 13 Cladonia, 
7 Sticte, 6 Pamelie, 5 Usneæ) so small a number in Kerguelen is rather 
surprising. 
The second feature is the floristic difference noticeable amongst the 
crustaceous species of the two areas. With the exception of the cosmo- 
politan Rhizocarpon geographicum, not one crustaceous species recorded by 
Zahlbruckner has been found in the Falklands, and very few are listed 
by Darbishire for Fuegia. The time has not yet come for drawing con- 
clusions based on such small species, but it would certainly appear that the 
lichen-flora of Kerguelen has not much in common with subantarctic 
America. The permanently saturated soil of Kerguelen is probably 
uniavourable to the growth of foliose species, and the Falklands have the 
advantage of proximity to the mainland, by means of which the flora, through 
reproductive bodies brought over by the prevailing westerly winds, may 
he constantly renewed. 
D. Fuxar—Little can be said with regard to this group in other parts 
of the subantaretie, Hennings (06) has given a careful account of the 
Kerguelen material brought back by the ‘Gauss, and this may be com- 
pared with the Falkland Islands and Magellan lists. The lists, however, 
consist mostly of micro-species, and it is evident that our knowledge is 
very imperfect. 
