186 Letters, Extracts, and Notes. [Ibis, 



Spotted Flycatcher (Muscicapa grisola). A clutcli of 5 

 from Kent, entirely without the greenish tinge, a compara- 

 tively rare occurrence with this species. — Ibis, Jan. 1916, 

 p. 187; Britisb Birds, vii. p. 251. 



Cuckoo (Cuculus canorits). Four eggs from Kent, and 

 one from Noithauts, all with Hedge-Sparrow's ; all dis- 

 tinctly erythristic. 



Nightjar {Caprimulgiis europmis). Four clutches from 

 various localities, showing pinkish ground. — British Birds, 

 vii. p. 254 ; Ball. B. O. C. xxiii. p. 24. 



Green Sandpiper (Totanus ochropus). A very reddi>h 

 clutch. At least one form of the eggs of this species has a 

 distinctly erythristic tendency. 



Wood-Sandpiper [Totanus glareola) . A clutcli of i from 

 Lulea. 



Kentish Plover {^^gialitis alexandrina). A clutch o£ 4 

 from Ilolstein, with erythristic tendency ; the green pigment 

 is, however, present in the innermost lime-layer, though 

 very slight. 



Lapwing {Vanellus vanellus). A clutch of 3 from Forfar, 

 showing true erythrism ; the green pigment usually present 

 in the innermost lime-layer is wholly absent. — Ibis, 1917, 

 p. 127. 



Herring-Gull (^Lurus argentatus) . A clutch of 3 very 

 beautiful eggs from Norway. This clutch differs from the 

 type eggs in the arrangement of the markings ; this appa- 

 rently often occurs with erythristic eggs. 



Common Tern (Sterna hirundo). Three clutches of 3, 

 and two of 2, each British ; all from same locality. These 

 are remarkably beautiful eggs, and vary in ground-colour 

 from salmon-pink to reddish-brown. These eggs were first 

 described by me in Bull. B. O. C. xxix. p. 45 ; British Birds, 

 vii. p. 256. 



Razorbill {Alca torda). Five eggs from various localities, 

 showing true erythrism. The greenish tinge usually present 

 in the innermost lime-layer in the eggs of this species is 

 quite absent, which is apparently of rare occurrence. 



