4 THE BRITISH WILLOWS 



and in the British Museum, wherein those have been examined 

 which are quoted below. 



Many sheets of the Exs. of Billot and C. Magnier have been seen 

 in the herbarium of Charles Bailey, F.L.S. ; J. E, Leefe's second 

 set (Sal. Exs.) has been seen in that and other collections, and I 

 possess his earlier set (Sal. Brit. Exs.). 



Few references are possible to the General Herbaria of the 

 British Museum or Kew, or to those of Borrer (at Kew), of the 

 Eoyal Botanic Garden, Edinburgh, or of Boswell-Syme, for want 

 of numbers. The numbered sheets of S. J. Enander's Sal. Scand. 

 and of the Sal. Exs. of Ad. Toepffer, both of whom have supplied 

 me generously with letterpress and specimens, and of the herbaria 

 of the late Eev. W. E. Linton (now in the possession of the Liver- 

 pool University) and of the Eev. E. S. Marshall, to whom I am 

 greatly indebted for very numerous specimens of his collecting 

 with notes, are frequently quoted. 



Synoptical Table of Species and Hybrids. 



The following arrangement is based largely on the order 

 adopted by N. J. Andersson in De Candolle's Prodromus, the main 

 divisions of which depend on the number of stamens, viz. 

 Pleiandrce, Synandrce, and Diandrce. He placed Fragiles and 

 Albce among the Pleiandrce because their other floral characters 

 connect them with that group ; and this is their right position, 

 though the stamens are only two, for three are very exceptional. 

 Synandrce are removed from the end of the list, where they were 

 placed by Andersson, next to alpine species (to which they have 

 no relation), to a position preceding the Diandrce, next to the 

 Viminales and Caprea, lowland plants for the most part which are 

 their nearest allies. S. lapponum is taken out of the Nivece, 

 having no great affinity with S. lanata, and placed in the Vimi- 

 nales, in accordance with the views of Wimmer, who pointed out 

 the many features which this species and S. viminalis have in 

 common. 



A. Pleiandrce. 

 Stamens 2, 3 or more ; bracts concolorous. 



i. Pentandrae. 



i. S. PENTANDRA L. 



ii. Amygdalinae. 



2. S. TRIANDRA L. 



subsp. Hojfmamiiana Sm. x viminalis. 



iii. Fragiles. 

 3. S. fragilis L. 

 b. hntannica B. White. x pe?itandra. 



subsp. decipicns Hoti'm. 



