

































. 



REA'ISION OF THE BRITISH WILLOWS. 371 



the $ are generally broader ; and, so far as I have seen, they 

 are constantly broader in proportion to their length, and henee 

 possibly belong to Wimmer's form ovalis. 



Salix vitellina, L., is reduced by Koch, Wimmer, Andersson, 

 &c. to the rank of a mere form of S. alba, distinguished only by 

 the colour of its bark and its generally narrower leaves, and said 

 to be often produced either by being cut over every year, or by 

 a diseased condition of the plant. Whether it be a diseased 

 condition or not, it certainly does not depend for its characters 

 on annual lopping; and, in addition to the colour of the bark, 



has several important structural differences to separate it from 

 ordinary alba. 



-The catkins are much more slender and proportionately, if not 

 actually, longer, with usually more scattered flowers, and remark- 

 ably long and narrow scales. The leaves are smaller and usually 

 of a paler or more yellow-green, and frequently less pubescent. 

 Boswell Syme thinks that the ovaries are always abortive ; but 

 whilst I have not had sufficient opportunities of studying the 

 plant to be positive, I am inclined to think that he is wrong on 

 this point. On these grounds, I consider that vitellina is worthy 

 of at least varietal rank. 



Fries thought that " 8. vitellina, L.," pertains to 8. fragilis. 



in Linne's herbarium are two specimens labelled by Linne " 5. 



titellina." To the <J Smith has put a " ? " and to the £ " alba ? " 



^he 6 has the long scales of vitellina ; the $ has short scales, 



but long narrow catkins; the bark in both is now purple-brown, 



while the leaves are too young to afford much information. On 



wnole, I think these specimens are nearer vitellina than 

 Epical alba. 



Whether 8. alba is native in Britain is perhaps doubtful, for, 

 Whilst usually planted, yet self-sown plauts occur. The var. 

 vitelhna is said to occur chiefly in osier-grounds, but in Norfolk 

 C*we (Smith's ' Engl. Fl.') thought it was " truly wild." 



X Salix vi amis, Fr. (S. fragilis x 8. alba.) 



o. viridis, Fr., may be taken as the central or typical form of a 



mow which presents a regular series of gradations between 8* 



fragilis on the one side and S. alba on the other. Consequently 



11 18 (!0U 8idered to be a hybrid between these two species ; but if, 



ndersson says (as has been already noticed under S.fragilis) 9 



ese two species are so connected in some parts of Asia that it 



uncult to separate the one from the other, it seems quite pos- 











■ 





