314 THE BOTANICAL EXCHANGE CLUB OF THE BRITISH ISLES. 



Moreover, the opinion of Tourlet, who makes Desetangsii a sub-species 

 of maculatum, does not lack a certain value, that our plant is often 

 very difficult to be marked off from the sub-species obtusiusculum 

 (Tourlet) of maculatum, and also in its vertical distribution is very 

 closely allied to the last-mentioned form. In the face of these 

 contradictory observations, it appears to me, with Bonnet, Coste, 

 Schinz, and others, to be the most advisable proceeding (contrary to 

 Frolich) to give H. Desetangsii a binomial rank. Its " hybridogenous " 

 nature will not thereby be in anywise denied. Desetangsii stands in 

 this connection like x Cireaea intermedia Ehrh. or x Mentha verticillata, 

 L. and x M. villosa, Huds. (M. nemorosa, Willd.), which likewise 

 (thanks chiefly to an abundant vegetative increase through the 

 formation of offshoots) occur abundantly without their parent species 

 or with only one of them, and sometimes surpass the area of distribu- 

 tion of one species. 



Hypericum Desetangsii Lamotte has been identified in Spain ! 

 France ! Belgium, England !* Germany ! Switzerland ! Austria ! and 

 Italy, and is certainly spread over the greater part of Europe. 



* Spontaneously in the garden of the Rev. G. B. Hooper at Cam- 

 borne, Cornwall, Dr Schinz, and first as British. 



There is also a valuable note on this plant by Dr Anton von 

 Frolich of Graz in the Oester. Bot. Zeit. 13, 1913. 



463. Tilia platyphyllos Scop., var. corallina Aiton Hort. 

 Kew. ii., 229, 1789. Differs from the type in its bright red branches. 

 First found in Britain by Bobart in Stokenchurch Woods. Ray's Syn. 

 1690. Not recently observed. Bicheno saw one tree there in 1824. 



464. T. europ^ a L. 1 T. cor data x platyphyllos. var. pallida 

 Wierzbicki in Reichb. Icon. Fl. Germ, vi., 58, t. 315, 1844, as a 

 species. Leaves not much larger than cor data, as broad as or broader 

 than long, yellowish or bluish green beneath. Readily distinguished 

 from cordata by its prominent tertiary venation ; flowers and fruit as 

 in type, Elwes & Henry British Trees. 



Elwes and Henry ( British Trees, 1665, 1 9 1 3) give the following 

 useful clavis to the three Limes : — 



463. T. platyphyllos. Branchlets and leaves very pubescent 

 with long hairs. Buds with three external scales. Cymes pendulous, 

 usually three-flowered. Fruit with prominent ribs ; shell woody and 

 hard. 



