( 508 ) 



N.W. Africa might uot be separable on account of the pnrer white under tail-coverts. 

 The series now collected by us does not bear this out, although some of the males 

 have remarkably white under tail-coverts. 



The iris is dull ochre, the orbital ring dull red, feet light brown. Bill black, 

 base of lower mandible pale (pale flesh, whitish). 



A number of these birds appear to winter in Algeria, while others are 

 doubtless migratory. We found them quite common near Algiers and Hammam 

 Meskoutine from the last week of January to the middle of February. 



Full clutches, of three eggs each, were foiind near Algiers on May 13 and 10. 

 The eggs, as is well known, vary very much, and our three clutches belong to three 

 quite different types : one clutch is pink, covered all over with faint pinkish brown 

 spots, another creamy white with large patches nf brown and underlying ones of 

 ashy grey, the third greenish white with olive-brown and greyish patches, this last 

 one resembling very closely the eggs of Acrocephalus streperus. The measurements 

 of the tirst clutch are IS'O x 14"u, IS x 14, and 18 x 14 ; those of the second 

 17"0 X 13-0, 17-7 X 13o and 17'3 x 13'o ; those of the third l6-7 x 14, I'J x 14-1 

 and lS-7 x lli-U mm. The first and third contained Cuckoo's eggs. 



84, 85, SO. Sylvia cantillans. 



{Si/lvia subalpina auctorum I) 



Formerly all " 8ubalpine Warblers " were supposed to be the same. In 1899 

 Erlauger noticed differences between his Tunisian and Herzegovina specimens, but 

 wisely refrained from giving a new name to eitLier of these forms. In 19iiG Tschusi 

 {Or/i. Julnb. 1900, p. 141,i, named the Tunisian form, but he apparently based his 

 disliuclion chiefly on comparison with !S.E. Eunqicau examples, which are quite 

 different, both from the topotypical cantillans (Italy), and the i^.W. African form, 

 and his description is by no means clear. In 191)9 Hartert {\^oij. pal. Fauna, i. 

 pjj. ;j90, o97_) separated three forms : 



Hi/lcia siibalpina subalpina : S.W. Europe and Italy. 

 ,, „ inornata : N.W. Africa, and 



„ „ albistriata : 8.E. Europe. 



Of these the last, albistriata, differs in size and shape of wing, while the other 

 two are very closely allied, and only ditt'er in the colour of the underside. Never- 

 theless, so far they seem to be easily sejiarable, and it is by no means impossible 

 that even more forms might be distinguished if sufficient series were compared. 



Examining our Algerian birds, we flud them to belong to all three races : 



Si/lcia cantillans * inornata Tsch. 



We found this race on the breeding-grounds near Batna and Lambese in May, 

 and also at Biskra. 



A male was shot at Tilrhempt on April lo. A few specimens were obtained 

 near Bordj (Jhegga and at Touggourt, but they were most probably on migration. 

 Jlr. Kiggeiibach collected this form at Fcnzou and Temeroui, in the S.W. Atlas in 

 Morocco, in the middle uf A]iril. 



This form has, apparently, always a more cinnamon colour on the underside 



* The uume cantillans is earlier than mbalp'tna, aad rtfera to this Sijecies, not to the UartfoiU 

 Waiblei'j us crrouuously suppofrcU by ilichiiiuiiU. 



