ORIGIN AND PRESENT DISTRIBUTION OF THE BRITISH FLORA. 421 



north of England only. The Alpine of Forbes or the Highland of 

 Watson includes a group of arctic plants. The nearest localities where 

 plants of this group are to be found are the Alps, Pyrenees, Scandi- 

 navian mountains, and arctic regions generally ; though they are mostly 

 or entirely absent from the warmer lowlands which separate such widely 

 severed districts. Watson's Germanic takes in plants found in the east 

 and south-east of England bordering the German Ocean, whence he 

 derives the name, and includes those plants called Kentish by Forbes, but 

 which do not seem to be deserving of a special name, as they are chiefly, 

 if not always, plants affecting a limestone or chalky soil, and which, in 

 part, occur elsewhere. The Atlantic types of Watson embrace plants 

 found in the west and south-west of England and in Ireland. In these 

 are included the Armorican of Forbes, which is characterised by a group 

 of plants found in Normandy, the Channel Islands, the south-west of 

 England, extending (in part) some distance along the west and south 

 coasts, and in the south-east of Ireland. This group is in reality 

 South European, reaching Normandy by crossing north of the Pyrenees. 

 The number of peculiar species continually decreases in passing in a 

 north-westerly direction from their original home in South Europe ; so 

 that while several which are in the Channel Islands are wanting in the 

 south-west of England, others which reach that corner fail to cross over 

 to Ireland.* A portion of this Atlantic type was separated by Forbes as 

 Asturian, because the nearest locality on the Continent whence it was 

 presumed by him that these plants had come was the Asturian mountains 

 of North Spain. They consist of six species of saxifrage : Saxifraga 

 umbrosa (cultivated as 'London Pride'), S. elegans, S.hirsuta, S. Geum, 

 S. hirta, S. affinis ; two heaths : Erica Mackaiana, E. mediterranea ; 

 Menziesia polifolia ; Arbutus Unedo (the " strawberry tree ") ; and Arabis 

 ciliata.f 



* Helianthemum polifolium, Tamarix gallica, Polycarpon tetraphyllum, Cor- 

 rigiola littoralis, and Bupleurum aristatum occur in Devonshire and Cornwall, but do 

 not extend into Ireland. The following are some which are to be found in the 

 Channel Islands, but not in England or Ireland : — Ranunculus ophioglossifol ius, 

 Sinapis incana, Helianthemum guttatum, Silene quinquevulnera, Centaurea aspera, 

 Gnaphalium luteo-album, Cicendia pusilla, Linaria Pelisseriana, Echiuni planta- 

 gineum, Armaria plantaginea, Orchis laxiflora, Scirpus pungens, Lagurus ovatus, 

 Cynosurus cristaius, Broinus niaximus, Gymnogramme leptopJiylla, Ophioglossum 

 lusitanicum. 



f Subjoined are a few selected plants in order to illustrate the sub-floras of 

 Watson : — 



1. British type. Betula alba, Corylus Avellana, Salix Caprea, Rosa canina, 

 Hedera Helix, Calluna vulgaris, Ranunculus acris, Trifolium repens, Lotus cornicu- 

 latus, Bellis perennis, Myosurus minimus, Urtica dioica, Lemna minor, Poa annua. 

 Pteris aquilina, Polygonum aviculare. 



2. English type. Rhamnus catJmrticus, TJlex nana, Tamils communis, Bryonia 

 dioica, Hottonia palustris, Chlora perfoliata, Sison Amomum, Linaria Elatinc. 

 Ranunculus par viflor us, Lamium Galeobdolon, Hordeum pratensc, Ceterach officina- 

 rum. 



3. Scottish type. Empetrum nigrum, Rubus saxatilis, Trollius europaeus, 

 Geranium sylvaticum, Habenaria albida, Ligusticum scoticum, Lithospermum 

 maritimum. 



4. Highland type. Azalea procumbens, Cherleria sedoides, ^ Veronica alpina, 

 Alopecurus alpinus, Phleum alpinum, Juncus trifidus, Sibbaldia procumbens, 

 Erigeron alpinum, Gentiana nivalis, Salix herbacea, Silene acaulis, Saxifraga 

 stellaris, Oxyria reniformis, Thalictrum alpinum, Rubus Chamaemorus, Epilobium 

 alsinifolium, Dryas octopetala, Alchemilla alpina. 



5. Germanic type. Frankenia laevis, Anemone Pulsatilla, Reseda lutea, Silene 



