Coloration of the Mouths and Eggs of Birds. 275 



Palaearctic Hypolais, Acrocephalus , LocusteJla, Cisticula, and 

 Sijlvia; Mr. Bates describes it for West African Cisticola 

 erythrops, Calamocichla rnfescens, Burnesia bairdi, B. leuco- 

 pogon^ Euprinodes nfogidaris, Apalis binotata (spots dark, 

 not black), Camaroptera griseoviridis, and Sylviella denti ; 

 and I have found it (or in slightly older birds the remains 

 of it) in south-east African Prinia mystacea (fig. 8), Cisticola 

 natalensis (fig. 6), C. cinerascens (fig. 10), Apalis thoracica, 

 Chlorodyta neglecta, and the Palaearctic Sylvia cinerea. 

 That is, it occurs in all the fourteen genera of the Sylviidae 

 described by Mr. Ingram or Mr. Bates, or observed by myself. 

 Locustella has a third spot, near the tip of the tongue. 



2. The " domino " mouth. Symmetrically-arranged black 

 spots on a pale palate. It is present with variations in many, 

 probably most, of tlie Estrildinre, such as Spermospiza gut- 

 tata, Pytelia nitidida, Poephila mirabilis, Hypargus schlegeli, 

 Lagonosticta rhodopareia (figs. 4, 5), Estrilda astrild, E. 

 nonnula, E. me/poda, E. atricapilla, Nigrita luteifrons, and 

 N.fusconota. All have this mouth, the resemblance between 

 the last six species being apparently particularly close, as 

 also that between the above Hypargos (figured by Bates) 

 and the Lagonosticta as noted by myself. 



3. The plain orange mouth with paler flanges (greenish- 

 yellow mouth in Tchitrea viridis) of all the Flycatchers but 

 one described by Mr. Bates — Fraseria ocreata, P edilorhynchus 

 comitatus, Erythrocercns maccalli, Trochocercus nigro-mitratus, 

 and Tchitrea. The exception was Chloropeta (figs. 9, 33), one 

 that I have myself noted, too, and will refer to again below. 



4. Plain yellow to orange, with paler flanges, is the 

 colouring of some, at any rate, o£ the English thrushes, 

 deeper in the Blackbird, paler in the Mistle-Tlirush (fig. 26). 



5. The scarlet-lake or crimson mouth with pale yellow 

 flanges of the nestling Weavers of my acquaintance — • 

 Hyphantornis jamesoni (figs. 13, 18), H. nigriceps, Sitagra 

 ocularia, Amblyospiza albifrons (fig. 1), and Coliuspasser 

 ardens (figs. 2, 3); also Pyromelana flammiceps according to 

 Bates. 



6. The only two Doves, the nestling-mouths of which 



