58 The Distribution of the Irish Flora. 
in the Marginal type 1 , one half of them being characteristic upland 
species ; this type is mainly alpine, calcifuge, or xerophytic, these 
sections being due to the numerous mountain groups, the absence of 
limestone and the sands of the coast respectively. Their distribution 
in Great Britain is very varied.—The Ultonian type includes 45 
species (e.g. Saxifrage oppositifolia, Circaca alpine, Cicnla virosa, 
Potamogcton filiformis), about 30 of which are hill or mountain 
species, both calcicole and calcifuge species being absent. In Great 
Britain this type is chiefly Highland and Scottish in distribution.— 
The Mumonian type has 66 species (e.g. Ranunculus Lenonnandi , 
Pinguicula grandiflora, Campanula TracJtclium, Clilora perfoliate ), 
more than half of them inhabiting pastures, light soils and dry 
places. They are markedly southern and western in distribution in 
Great Britain.—49 species (e.g. Lepidium Jiirtum , Trifolium 
glomeratum, Cynoglossum officinale , Scilla verna) belong to the 
Lagenian type, which is to a great extent xerophytic in character. 
Its distribution in Great Britain is chiefly “ English.”—The 
Connacian type has 63 species (eg. Taxus baccate , Adiantum 
Capillus-Veneris, Habenaria intacta , Erica mediterranea) and is 
chiefly made up of calcicole, mountain and bog-plants. The 
distribution of the group in Great Britain is quite heterogeneous. 
It is interesting that certain plants of wide distribution in 
Ireland are absent from definite areas; thus Drosera auglica is 
absent from the south-eastern counties alone (Anti-Lagenian type), 
whereas Oenanthe Phellandrium dies out along the mountainous edge 
of the island. These plants are best included in smaller types of 
distribution and termed according to their most conspicuous feature 
“Anti-Ultonian,” “Anti-Central,” etc. 
The aliens were generally found to possess a discontinuous 
range, a large number being widely distributed, whilst others fall in 
with various types of distribution. These latter are chiefly aggre¬ 
gated in the south and east of the island; Mr. Praeger accounts for 
this in the following words: “The great Leinster anticline is an 
important factor in Irish plant distribution, and a phytological 
boundary of marked character is formed by the line where its 
uplands sink into the Central Plain, and by the prolongation of that 
line northwards and southwards.” 
Very little can as yet be said as to the causes which have led to 
the present distribution of the Irish flora. The effect produced by 
the nature of the soil is sufficiently obvious, but with regard to 
1 Maritime plants, which are generally distributed round the 
coast, are considered to belong to the General Type.. 
