PHYLLOSCOPUS. 423 



Genus PHYLLOSCOPUS. 



The Willow-Warblers were originally included by Linnaeus in his genus 

 MotaciUa, and were afterwards separated by Scopoli and placed in his 

 genus Sylvia together with the rest of the Warblers. In 1802 Bechstein 

 created thr* subgenus Asilus in his ' Ornithologische Taschenbuch/ p. 173, 

 for the reception of the Willow- Warblers ; but as, in 1767, Linnaeus had 

 already applied that name to a genus of insects in his ' Systema Naturae ' 

 (i. p. 1006), it cannot be also applied to a genus of birds. In 1816 Koch, 

 in his ' System der baierischen Zoologie/ i. p. 158, made an equally unsuc- 

 cessful attempt to erect a genus for the reception of the Willow- Warblers, 

 selecting for this purpose the name of Ficedula, a name which is open to 

 three objections. In the first place, the MotaciUa ficedula of Linnaeus is 

 not a Willow-Warbler, whatever else it may be ; in the second place, in 

 1799 Cuvier made a genus Ficedula to contain the Flycatchers; and, in the 

 third place, the genus Ficedula of Brisson appears to be synonymous with 

 the genus MotaciUa of Linnaeus, and its type was probably a young or 

 female Pied Flycatcher. In the following year Forster, in his ' Synoptical 

 Catalogue of British Birds/ p. 54, was equally unfortunate in adopting the 

 specific name trochilus, which Linnaeus gave to the Willow- Warbler, as 

 the name of his new genus, regardless of the fact that this name had 

 already been applied by Linnaeus (Syst. Nat. i. p. 189) to the Humming- 

 birds. In 1826, however, Boie succeeded in finding a name which is open 

 to no objection, and in the 'Isis' for that year (p. 972) established the 

 genus Phylloscopus for the Willow- Warblers, making P. trochilus the 

 type. 



The Willow- Warblers are a group of about five-and-twenty little birds 

 so nearly allied to the typical Warblers (Sylvia), the Tree- Warblers 

 (Hypolals), the Reed- Warblers (Acrocephalus) , the Grasshopper Warblers 

 (Locustel/a) , and the Grass -Warblers (Lusciniola), and especially to the 

 Indian Flycatcher Warblers (Abrornii), that it is impossible to draw a 

 hard and fast line between any of these genera, except by arbitrarily 

 choosing some character and making it the standard of separation. In 

 such nearly allied genera, where the intermediate species have not yet 

 become extinct, ornithologists must accept with gratitude any cha- 

 racter, however trivial, which seems to classify the species into natural 

 groups. 



The principal characteristic of the Willow- Warblers is their semi- 



