122 JOURNAL OF THE PLYMOUTH INSTITUTION. 
northerly direction I have seen it near Launceston, and it is said to 
have been found recently in the neighbourhood of Bideford, North 
Devon. The most northerly point that it reaches in this direction 
would be that also of its whole world range. How desirable then 
to ascertain quite clearly its precise northern line of limit within 
our confines. Its eastward one also, from Ivybridge up through 
Devon, should be clearly traced out. The record of this at all as 
a British species arose from my sending specimens to the Thirsk 
Botanical Exchange Club, gathered in the neighbourhood of Ply- 
mouth, now nearly twenty years ago. The plates of it that shortly 
after appeared in the Journal of Botany and English Botany 
(ed. 3) were both drawn from local specimens. Looking at the 
whole Continental range of this species, together with its entire 
absence from Central Europe, we may, I think, consider its occur- 
rence in England to be due in a great measure to climate, and infer 
that a degree of cold beyond what we experience in West Devon 
and Cornwall would not suit it; nor that, on the other hand, would 
an arid climate, such as prevails in tracts far removed from the damp 
and fogs brought by the ocean. It is probable this plant may yet 
be found in Ireland, the southern and south-western portions of 
which afford the conditions it seems to require. 
One of the rarest of our plants, Hypericum linariifolium, Vahl., 
occurs near Plymouth only in two places, but appears also in 
patches about the Teign river, and is said to have been found at 
Cape Cornwall, near St. Just. Beyond this it is unknown in Great 
Britain. Its Continental distribution corresponds somewhat with 
that of H. bceticum, but, besides growing in the Canaries, Spain, 
and Italy, it occurs in the Channel Islands, France, and Turkey. 
As climatal influences have probably much to do with the range of 
bceticum in Britain, so perhaps have they with that of this also, 
though the situations it affects are just the opposite; for whilst 
bceticum is at home on the boggy margin of the meadow stream, 
bearing its little tribute of waters from the hillside copse above to 
the river in the valley below, linariifolium exists on the dry bank 
or rocky declivity warmed and brightened day after day by the 
full beams of the noonday sun. In very dry summers this partiality 
of the latter for such spots becomes a positive disadvantage to it, 
rendering it liable to be injured or even killed by drought. Prob- 
ably however, in damper spots, or those colder through shade, the 
frosts of winter would act with a more strongly injurious force than 
