ADDITIONAL LIST. 467 
but my sins in that line have not gone so far as to encumber our 
books with names and localities for evanescent plants seen as 
single stragglers, or more numerously for a single season only. 
Here, it is wished to notice those only which have already been 
noticed elsewhere. 
4. Eatincts.—This is a very small group, while limited to native 
plants which are known to have become extinct; say, like Carex 
Davalliana, in Somerset. When we take in also other plants 
reported for localities at former times, but at present not found in 
the places named, the group becomes enlarged; and no absolute 
line of separation can then be traced between it and the temporary 
casuals, on the one side, or between it and the errors, on the other 
side. If a plant, otherwise not known as British, have been 
reported in a place once only by a supposed eye-witness, and 
cannot be again found in the same place when sought by others, 
there would seem fair reason to suspect an error or misnomer by 
the “eye-witness.” The alternative would be, to regard the 
plant as a temporary casual on the spot indicated; while there 
would still also remain a bare possibility of a real extinction of a 
native plant, made no longer so. In this way, the small group of 
extincts lapses into the two others, or stands with undefined 
limits between them. Some truly English plants are gradually 
decreasing in the number of their localities, and in their own 
numbers in localities where they still linger. The Scirpus 
parvulus, so small and easily overlooked, may not really have 
been made extinct. Cypripedium Calceolus and Orchis hircina 
still exist, though in great risk of extirpation by gardeners and 
botanists. Potentilla rupestris is reported to be now (1869) very 
rare in its only locality, on Craig Breiddin. It is doubtful whether 
Eriophorum alpinwn is extinct or not so. Like the Hierochloe 
borealis it may really turn up somewhere else in Scotland, away 
from its one county of Forfarshire, where it was destroyed by 
drainage. Professor Balfour’s alleged habitat of Sutherland 
should belong to the category of errors, rather than to the present. 
While some actual extinctions among plants are probable, both 
