AVES. 
05 
birds ; thus in the Psittaci, AlcedinidcB, and Paridce, 'where the 
hens are as eonspieuous as the coeks, the sitting-birds are eon- 
cealed^ while in the Cotingidcs, PipridcBy and Tanagridce the hens 
are soberly coloured and sit exposed on their nests. The author 
then proceeds to account for these facts, which he believes are 
owing to the greater necessity of protection to the hen than to 
the cock during incubation. He had previously found a simi- 
lar state of things in diurnal Lepidoptera, and this made him 
apply the same solution in the case of birds. He accepts Mr. 
Darwin^s doctrine of sexual selection to explain the brilliant 
colours of the males of various animals ; but Mr. Wallace main- 
tains that the fact of both sexes in many species being equally orna- 
mental shows that there is a tendency on the part of both to inherit 
bright hues, and that when they are entirely wanting in the female 
it is because the possession of them would be injurious to her. 
Further, he denies, on the grounds already mentioned, that the 
mode of nidification in birds depends on the colour of the hen, 
but upholds the contraiy opinion ; since colour is known to 
be the most variable and easiljr modified character possessed 
by organized beings, consequently it serves more than any 
other the purposes of protection, and must be regarded as one of 
the most important agents in adapting animals and plants to the 
changes ever taking place in their environment.^^ [Vide supra, 
Argyll, Duke of, and Murray, Andrew.] 
The eggs of some twenty species of South-African birds described. E. L. 
Layard, Ibis, 1868, pp. 242-247. 
Steatornis caripensis, its egg figured (woodcut) and described. P. L. Sclater, 
P. Z. S. 1868, pp. 73, 74. 
Caprimulgus {Stenopsis) hifasciatus, its eggs figured. J. f. 0. 1868, Taf. ii. 
fig. 3^. 
Menura superha, its nest and eggs described. E. P. Ramsay, P. Z. S. 1868, 
pp. 49-51. 
Hirundo alfredi (sp. n.), its eggs figured. J. H, Gurney, IbiJJ 1868, p. 163, 
pi. iv. Nest described, E. L. Layard, tom. cit. p. 243. 
Cisticola schoenicola, its eggs described (c/. Zool. Rec. ii. p. 91). W. E. 
Brooks, tom. cit. pp. 130, 131. 
Do7iacola castaneothorax, its nest and eggs described, E. P. Ramsay, totn. 
ci^.pp. 231-233. 
The curious parallelism of the aberration from the normal colouring in the 
egg of Tetronia hrachydactyla among the Fringillmm, and in the egg of Melo-^ 
spiza lincolni among the Spizcllinccj noticed. H. 13. Tristram, tom. cit, 
p. 206. 
Nncifraga caryocatactcs, its breeding in Switzerland. G. Vogel, J, f. 0. 
1868, p. 329. 
Caccabis grccca and C. saxatilis, the difference in their eggs. H. B. Tris^ 
tram. Ibis, 1868, pp. 213, 214. 
^ The accompanying letterpress is at page 382, but did not appear within tlio 
year 1868. 
1868 , [yol, V.] V 
