lilNNEAN SOCIETY OF LONDON. 89 



bridf/ease, II. peltatum, and Lastrcea cemula, all Atlantic species 

 which are also found in Ireland. The Atlantic element is also 

 prevalent among the few southern species which are confined to 

 the western part of Great Britain, Meconopsis cambrica, Arabis 

 stricta, Helianthemum guttatum, and Trichomanes radicans, of which 

 the last but one is the only Mediteri'anean element. 



" If we turn to the remainder of the more limited* species of the 

 southern stock (excepting those which are confined to Ireland) we 

 find the Mediterranean element dominant, there being 33 of it 

 against 18 of the Atlantic type. They range as follows : — 



*' Pembroke in the west and Norfolk in the east mark ofi" a zone 

 which is particularly rich in Mediterranean forms, the maximum 

 of them occurring in the Cornish peninsula. It is characteristic 

 that of the 25 southern species confined to the south of England 

 oidy three reach Ireland, and two of those are Atlantic, namely 

 Eu/jhorbia hiberna and Simetliis iilanifoUa. 



"The southern species which are generally diffused through 

 Ireland and, at the same time. Great Britain have alread}^ been 

 enumerated. To them have to be added Cotyledon Umbilicus and 

 Lastrmi anmda as general in Ireland, but more restricted in 

 Great Britain. The majority of them (7) are Atlantic. So are 

 also, with a single exception, the follow iug ten species, each of 

 which is recorded from 16 to 30 of Praeger's divisions: Lepidium 

 lieterophiiUam, Hypericuvi elodes, Erodimn moscJiaUim, Vlex Gallii, 

 Sedum aii;/licum, Rubia peregrina, Scntellaria minor, Orobanche 

 Hedera', Iris foetid issim a, Hymenophiilhim tunbridgense. 



" Among the species with more restricted distribution in Ireland 

 the Mediterranean element gains in number, but it nowhere out- 

 numbers the Atlantic, as it does in the southern counties of 

 England, the nearest approach to equalisation being in Cork West. 

 The Atlantic share of the Southern element predominates therefore 

 over the Mediterranean throughout Ireland. The main area o£ 

 the southern portion of the Irish flora with 18 to 29 species per 

 division is in the south, then in the west as far as Galway, and in 

 the east as far as Dublin. In the extreme south-west (Kerry and 



=*= Eecorded in the 'London Catalogue' from 1-25 vice-counties. I count 

 51 species as belonging to this class. 



