BOTANY 



years. The water level of the Pool has been so raised as completely to 

 cover the ground where this humble plant grew, and it is to be feared 

 that it must now be included amongst the extinct species of the county. 

 The occurrence of Trichomanes radicans near Tintagel has been much 

 questioned in botanical circles, but the letter from Mr. Everard F. im 

 Thurn in Nature, 27 April 1871, leaves no reasonable room for doubt 

 that it was really gathered in that locality. 



A few plants have been included in Cornish lists through miscon- 

 ception. Until stronger evidence than we already possess is forthcoming 

 the following must be accepted with considerable reserve : Thalictrum 

 Kocbii, Heliantbemum marifolium, Geranium syl-vaticum, Rbamnus catbarticus, 

 Trifolium stellatum, Saxifraga ste//aris, Cicuta virosa, CEnantbe Pbellandrium, 

 Galium Cruciata, Gnapbalium luteo-album, Senecio squalidus, Arnoseris pusilla, 

 Hieracium corymbosum, Campanula latifolia, Primula farinosa, Veronica 

 spicata, Melampyrum sy/vaticum, Lathrcea Squamaria, Suceda fruticosa, 

 Damasonium stellatum, Ryncbospora fusca, Asplenlum fontanum, A. septen- 

 trionale, Opbioglossum lusitanicum. 



Recent investigations have not only added many native species to 

 the flora of the county but have shown that several foreign plants have 

 secured a permanent footing, and will have to be accounted for in future 

 handbooks of the British flora. Erysimum repandum has long been known 

 near Launceston in goodly numbers and occurs more sparingly at Fal- 

 mouth and Penzance. Lepidium virginicum springs up annually at Par 

 and Penzance, and for more than a quarter of a century Rapistrum 

 rugosum has claimed two or three spots at Falmouth. Impatiens Roy lei 

 grows by the thousand in the valley between Liskeard and Looe, and 

 more sparingly though none the less luxuriantly near Tintagel. Aster 

 Novi-Belgii is a striking plant at Looe and Par, where it has long been 

 growing. Matricaria discoidea is perhaps the most astonishing case of 

 an alien becoming a denizen. First appearing at Falmouth less than a 

 decade ago, it has now become a pestiferous weed all over the district, 

 being found in fields and by the roadside in at least half a score of 

 parishes. Mimulus Langsdorffii, M. moscbatus, Omphalodes verna and 

 Pbalaris aquatica are other foreign subjects which have shown adapta- 

 bility to Cornish soil. 



To say Cornwall possesses more specialities than any other English 

 county is to repeat what most botanists already know. The last county 

 geographically, it is the first botanically. Here Brassica Cbeiranthus, a 

 plant still restricted by the London Catalogue to the Channel Isles, has 

 been flourishing for half a century and more. Here only in Great Britain 

 grow Lavatera sy/vestris, Cytisus scoparius var. prostratus, c Trifolium Molin- 

 erii, T. Bocconi, Ornitbopus ebracteatus, Erica vagans, Echium plantagineum, 

 Pinguicula grandiflora, Herniaria ciliata, "Juncus fygmaus, J. capitatus, 

 Bromus rigidus, Cbara fragifera and Nitella hyalina. With Devon it has 

 shared exclusive possession of Hypericum undu/atum, H. /inartfo/ium, Pyrus 

 cordata, Pbysospermum commutatum, Lobelia urens, Scropbularia Scorodonia, 

 Euphorbia hiberna. Iris tuberosa and Romulea Columns. 



51 



