ORTHOTRICIXA FOUND IN AYKSHIKE. 347 
species of Ortliotricha have a singular power of selection in regard to 
habitiit. Some are restricted to Ash-trees, one to Elders, another 
fovours Limes, another Willows ; some, again, prefer isolated trees, 
others trees in woods. 
It is singular that the two species 0, samtlle and O. anomaluniy long 
confounded till Dr. Wood showed the distinction, between tliem, 
should grow one on limestone the other on trap. 
The following list contains the rarer species of the other genera 
which have been found in this locality. The nature of the soil accounts 
for the absence of many species. There are no extensive marshy 
tracts; there is an entire absence of sandy hollows; we therefore do 
not find many of the species of Hypia^ Sphapta, and Br^a found in 
Lancashire and Cheshire. 
The species marked with an asterisk are characteristic of particular 
habitats, and indicate the presence of species that are generally found 
associated with them. Thus Sypnum condematim implies the presence 
in the hill gullies and bogs where it is found, of Sypmm commutatnm, 
Brynm pseudo-triqiietnim^ B. bimtim^ etc. 
Bartrarnia arcuata fniits freely on gully slopes. The female moss 
is the scarcer. Near Loch Doon I found another more fruitful station. 
It is ripe in the month of March, 
^Barlramia ithypliylla, 
Brymn obeomcum^ not at all rare here. I think this a good, 
though a somewhat difficult species. Mr. Wilson gathered, in com- 
pany with it, Bryiim miirale (Wils. MSS.) when with me here in 
1861 : I do not know this species, and have therefore not been able to 
identify it in the district. Bryum ohcordcum fruits later than its ally 
Bryum capillare* 
CrypJicea heieromalla, on Ash-trees. 
^Fissidens pnsillus, on a wettish sandstone wall, in company with 
Seligeria recurvata, 
Grimmia Donlana, Hedwigia ciliata fruits very freely in company 
with this beautiful moss. 
Grimmia tricopJiylla fruits very sparingly here : near Werayss Bay, 
on the Firth of Clyde it fruits most abundantly and beautifully. 
^Gymnostomum teniie. 
Hypnum brevii'ostre^ fruits in very great abundance here, in company 
Hypn 
2 A 2 
