T9o6. Prakgrr. — On the Botany of Lou^h Carra. 213 
baccata occurs occasion all}^ Hieracium iriciwi had at least 
one station. Another Havvkweed, now out of flower, I brought 
home to grow. Erica cinerea grew and flourished on the bare 
limestones. The absence of Euphrasia Salisburgensis was 
noticeable. On our journey to I,ough Carra we had found it 
abundant near Clonbur, and traced it northward nearly to 
Ballinrobe ; but about Lough Carra we did not meet with it. 
The Calcifuge Flora. — Though not actually touching the 
lake shore, we turned westward for half a mile out of Partry 
to note the change of flora caused by the substitution for 
limestone of Carboniferous Sandstone. This is very marked. 
On one side of a narrow shallow valley rise green limestone 
bluffs, clothed with Sesleria, Chlora, and Carlina. On the 
other are dark-brown heathy knolls, covered with Erica, 
Calluna, and Dabeocia in profusion. The river which divides 
East from West Mayo is here still half a mile distant, so this 
furnishes a very satisfactory third East Mayo station for the 
last-named. With it, among the heather, grew ListeJ'a cordata 
at an unusually low elevation — about 100 feet above Ordnance 
datum. 
Cultivated Area, — At Ballintober Lychnis Githago grev/ 
among crops, and Tanacetum vulgare in a rough field. 
Anthemis Cotiila and Etiphorbia exigua occupied roadsides 
near Partry, where also Lolium temulentum was gathered, and 
Inula Heleniurn in a rough field at Carrownacon. Matricaria^ 
discoidea lines every road and lane right round the lake. 
Injitie7ice of Birds.— On several islands, such as Bush Island 
and Illanatran, Black-headed Gulls and Terns breed, but 
without effect on the flora. On a small rocky wooded islet 
south-east of Castle Carra, however, there is a large colony 
of Black-headed Gulls, which largely control the flora there. 
The birds breed not only on open rocks, but on flat rocks 
among dense bushes. The trees and certain other plants, 
such as Phragmites, seem benefited by the guano, and flourish 
exceedingly. Other usual plants of the islands are missing, 
and have presumably been exterminated. A third set of 
plants have been introduced by the gulls. These include 
Stellaria media, So7ichus asper, Polygonums and Atriplices, 
Urtica dioica^ the cultivated Oat, Matricaria iiiodora, and even 
M. discoidea. 
