A HISTORY OF CORNWALL 



with the Upper Tamar District. At South Petherwin the Lower Devonian are exposed and 

 occupy the greater part of this district. West of the Lynher a small portion of the Bodmin 

 Granite Boss is included ; on a much smaller scale the same rock appears at Kit Hill and 

 Gunnislake. At Torpoint, and on the coast a little to the west of Rame Head, small patches 

 of limestone of an inferior character crop out from the argillaceous slates. They are very 

 restricted both superficially and in depth, and certainly have no appreciable influence on the 

 flora. Beds of greenstone and trappean rock traverse the Upper and Lower Devonian systems, 

 while the granite and the Lower Devonian encircling it are intersected by short elvan 

 courses running from east to west. 



As might be expected from a consideration of its physical features this slice of the county 

 offers many attractions to botanists. Rubi are represented here more largely than in any 

 other part of Cornwall, the result in a great measure of the good work of Mr. Briggs. Ran- 

 unculus auricomus, R. arvensis, Viola ericetorum, Silene nocttflora, Trifolium glomeratum, T. agra- 

 rium, Lathyrus sylvestris, Sedum album, Pimpinella major, Specularia hybrida, Linaria purpurea, 

 Zostera nana, all rare in other parts of Cornwall, have been gathered in the lower half of this 

 district. In the upper half Physospermum commutatum stretches right across the country from 

 Halton Quay on the Tamar to the western boundary-line. Sisymbrium Thalianum, not 

 recorded from west of Bodmin, is common on walls and dry banks around Torpoint and Rame, 

 and Hypericum undulatum occurs in most marshy places. On the dry slopes above Whitsand 

 Bay Lotus angustisslmus and L. hispidus keep each other company, the latter being the more 

 abundant. Along the banks of the river at St. Germans and Tideford large cushions of 

 Atriplex portulacoides are scattered over the beds of Salicornia herbacea and Suteda maritima. 

 Sandy soil near Notter Bridge gives a home to Scirpus sylvaticus, and in a large marsh on the 

 left bank of the Tidy just below Tideford, as well as in a salt marsh at Cotehele and a mud- 

 flat below Danescombe, on the Tamar, Alopecurus bulbosus is very abundant. The muddy 

 banks of the Tamar between Calstock and Morwellham is the one tract in Cornwall where 

 grow Scirpus triqueter and C. carinatus. The following are also unrecorded for any other 

 county division : Viola odorata x hirta, Rubus erythrinus, R. grains, R. silvaticus, R. Boraanus, 

 R. tbyrsiger, Crepis nicceensis, Campanula Trachelium, Atropa Belladonna, 



Until recorded from this district in 1870 by Mr. Briggs, Pyrus cordata was not known as 

 a British plant. Orobancbe amethystea was also added to the British flora in 1845 by its dis- 

 covery along Whitsand Bay by Rev. C. A. Johns. Attention is directed to the fact that five 

 broomrapes have been found in a small area in this division. 



A damp meadow near Weir Head furnishes a luxuriant crop of Poterium officinale. 

 Occurring but sparsely west of this division until the Lizard peninsula is reached its presence 

 by the Tamar in such profusion is a matter of considerable interest. Vicia lutea, Spiraa 

 Filipendula and Orobanche rubra, three other well known Lizard plants, crop up here also. 



Jacob's West Devon and Cornwall Flora (1837) mentions Nasturtium palustre for the 

 banks of the Lynher and Polycarpon tetraphyllum for Port Wrinkle, but both plants have long 

 disappeared from the district. Euphorbia Peplis was last seen on Seaton sands by Mr. F. P. 

 Pascoe in 1847, and E. platyphyllos known to grow at Torpoint in 1842 long ago took its 

 departure. Whether erroneously recorded or whether it has died out is difficult to say, but 

 no one appears to have seen Trifolium suffocatum at Crafthole since Jones placed it on record 

 in his Botanical Tour (1820). Quite rightly we think did Mr. Briggs warmly inveigh against 

 the ruthless collecting of certain grabbers whereby Cornwall was robbed of its only patch of 

 Potentilla argentea. It was found by Mr. Briggs at Trevol in 1865 and continued in occupa- 

 tion of the spot until 1878, when it was entirely lost sight of. 



SPECIES AND VARIETIES WORTH NOTING IN THE LOWER TAMAR DISTRICT 



Helleborus viridis, Linn. Brassica oleracea, Linn. Dianthus Armeria, Linn. 



Berberis vulgaris, Linn. - alba, Baits Stellaria umbrosa, Ofiz. 



Papaver hybridum, Linn. Diplotaxis muralis, DC. Buda rupestris 



Meconopsis cambrica, Vig. Lepidium ruderale, Linn. Hypericum hircinum, Linn. 



Glaucium flavum, Crantz campestre, R. Br. calycinum, Linn. 



Neckeria lutea, Scop. Thlaspi arvense, Linn. dubium, Leers 



claviculata, N. E. Br. Teesdalia nudicaulis, R. Br. - montanum, Linn. 



Barbarea intermedia, Boreau Cakile maritima, Scop. Malva pusilla, Sm. 



Erophila praecox, DC. Raphanus Raphanistrum, Linn. Linum usitatissimum, Linn. 



Cochlearia anglica, Linn. - maritimus, Sm. Geranium striatum, Linn. 



Erysimum cheiranthoides, Linn. Polygala oxyptera, Reichb. pyrenaicum, Burm.jil. 



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