330 ON SAFARI 



extremely late in reacLing England this year, but arrived in 

 markedly smaller numbers than I ever before remember. Thus 

 the Willow-Warblers (and Sand-Martins also) failed to appear 

 in Northumberland till May 1 — the former a fortnight, the 

 latter a month, overdue. No Spotted Flycatchers showed up 

 in my garden at Houxty till May 11; while Sedge-Warblers 

 and Tree-Pipits came together four days later — all long past 

 their customary dates. The paucity of their numbers this year 

 was also equally marked. The diminution in each of the four 

 specific cases could certainly not be estimated at less than a full 

 half: while as regards others of our summer- warblers, especially 

 Whinchats, the apparent loss mounted up to quite two-thirds of 

 their normal numbers. 



The subject is more fully treated in my Bird-life of the 

 Borders on Moorland and Sea (Second Edition), and a possible 

 explanation of such phenomena Avill be found suggested at 

 pp. 125 et scq. I venture to hope that every field-naturalist will 

 have read that work — and in no sense of paltry profit to me, 

 but solely for his own benefit and enjoyment. 



Shrikes 



In Europe we have but five or six species, while Africa 



boasts a dozen genera — a few of which may be mentioned 



here — 



Lanius. An overflow from Europe. Our British Red-backed 

 Shrike (Z. coUurio) occurs right through Africa in winter 

 as far south as Gazaland (inland of Delagoa Bay), and 

 has been recorded from Ruwenzori and elsewhere in 

 British East Africa. Mr. Jackson writes : " Very plenti- 

 ful in Rift Valley in March and early April." The 

 Lesser Grey Shrike (X. minor) also visits Africa in 

 winter ; but that continent only possesses one Lanius of 

 its own — Z. mackinnoni. 



Laniarius. An exclusively African genus, including a dozen or 

 more species, none of which I met with. 



Bush-Shrikes — Dryoscopus. Also purely African, numbering 

 about twenty species. B. nandensis, one of the many new 

 species discovered in East Africa by Mr. Jackson, is 

 figured at p. 174, from the plate in Ibis, 1901, p. 41. 



