217 



EUPHRASIA VIGURSII, sp. n. 

 By F. Hamilton Davey, F.L.S. 



(Plate 486.) 



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In the course of a few notes appearing in this Journal for 1906, 

 pp. 131-2, I referred casually to a Euphrasia which I had gathered 

 at Porfch Towan, approximating towards E. Rostkoviana, but which 

 the Kev. E. S. Marshall considered to differ materially from all 

 described British forms. About four months after finding the 

 plant, I sent several dried specimens to Prof, von Wettstein, at 

 Prague, but as, unknown to me, the monographer of the genus 

 Euphrasia had previously taken up his abode in Vienna, I have no 

 doubt my package failed to reach him. 



In September, 1906, while rusticating among the breezy up- 

 lands of the Dartmoor, South Devon, my friend, Dr. Vigurs, found 

 an Eyebright with the same deep purplish or violet-blue flowers as 

 my Porth Towan one, but much more slender in stem, branches, 

 and leaves, more abundantly covered with gland-tipped hairs, and 

 with the teeth of the leaves and bracts obviously more acute. 

 About the same time another friend and enterprising co-worker, 

 Mr. W. Tresidder, found in great abundance in Perranzabuloe 

 parish, between Newquay and Perranporth, a plant in every detail 

 agreeing with Dr. Vigurs's. My impression was that we had two 

 species awaiting identification, or at any rate a species and a 

 variety ; but, as the sequel shows, what we had under consideration 

 were really only two form3 of the same species. Through the kind 

 services of Prof. Hans Schinz, of Zurich, I was able to place in the 

 hands of Prof, von Wettstein a number of specimens of each form, 

 and his report shows that our Euphrasia is not only new to 

 Britain, but, as far as Prof, von Wettstein is aware, also new to 

 science. The following is a translation of the Professor's interest- 

 ing letter : — 



" The plant gave me much trouble, and has forced me to go 

 through the whole of my English Euphrasia material. The result 

 of this exact examination is that I cannot make the plant agree 

 completely with any one described species. It comes nearest to 

 E. Rostkoviana, though it is not nearly so hairy, and is altogether 

 smaller in all its parts, including the corolla. The only other 

 Euphrasia with which it can be compared are E. brevipila and E. 

 occidentalis Wettst. With E. brevipila it agrees in the size and 

 colour of the flower ; but it certainly is not that species, the glands 

 of which are too characteristic and constant to be mistaken. 

 E. occidentalis has still smaller flowers, and never such long-curled 

 glandular hairs as the plant in question. Moreover, E. occidentalis 

 belongs to the same group as E. curta and E. nemorosa. 



"How, then, shall the plant be named? To call it E. 

 Rostkoviana is impossible ; and without a knowledge of its distri- 

 bution I should not care to describe it as a new form. The latter 



Journal op Botany. — Vol. 45. [June, 1907.] r 



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