Praeger — On Types of Distribution in the Irish Flora. 21 



accumulation of vegetable matter, in woods, and mucii more in bogs, 

 which are largely developed in the Irish limestone districts. On the 

 other hand, no natural process is at work in this country producing 

 a calcareous soil in districts devoid of limestone, except on coastal 

 sands, where shelly aceumulations may have a distinct effect on the 

 flora. 



Glancing at the map, it will be seen by comparison with map 8 

 that, as contrasted with the distribution of limestone, the range of 

 the calcifuge flora is quite normal. It reaches its maximum on the 

 old non-calcareous rocks that stand grouped around the coast ; its 

 minimum in the Limestone Plain. The absolute minimum is reached 

 in "Westmeath, the only division in Ireland which can be said to be 

 altogether under the sway of the limestone. It will be noted that in 

 Clare, where the calcicole flora attains its greatest development, the 

 calcifuge flora is also at high- water mark ; but in the rich and 

 remarkable flora of that varied county, almost every group, whether 

 English or Scottish, Atlantic or Germanic, calcicole or calcifuge, 

 attains or approaches its maximum ! 



Considering generally the series of maps showing the range in 

 Ireland of the "types" of Great Britain, it will be seen that we 

 have really three topographical groups to deal with : — 



(1) English and Gekmanic, the latter a peculiar and intensified 

 section of the former. A southern group, often light-soil and often 

 calcicole in their proclivities. The Germanic plants represent the 

 xerophile and thermophile element in the flora of England, and are 

 congregated where a comparatively continental climate produces hot 

 and diy summers. In Ireland these groups are concentrated along 

 the east and south-east coasts, where position, soil, and climate 

 apparently account for their predominance ; and in the Clare district, 

 where the warm dry limestone pavements probably form the attraction. 



In refening the paucity of " Germanic" plants in Ireland to the 

 breaking down of the Irish-English land-connection prior to that of 

 the English-Continental, the editors of " Cybele Hibernica," ed. ii.. 

 remark (p. xliii) : — "The advance guard of aggressive species, the 

 British type and a large section of the English type, had time to push 

 westward into Ireland before its eastward land-connections were 

 broken down; but the rear-guard of more slowly spreading species 

 found their westward progress checked by thejand subsidence which 

 created the Irish Sea. The mass of this rear-guard was probably 

 formed of the Germanic type plants, a group so little aggressive in 



