490 
INDEX 
Shell-mounds, ancient, in the Aleutian 
islands, 437 
Shufeldt, Dr., on affinity of goat- 
suckers and owls, 123 (note) 
Sickle-bill humming-bird, 321 
Sidgwick, Mr. A. on protective 
colouring of moths, 46 
Simocyonide, 165 
Sitta, sexual colouring and nidification 
of, 126 
Sittella, sexual colouring and nidifica- 
tion of, 126 
Size, correspondence of in tropical 
flowers and insects, 406 
Skull, the Calaveras, 447 
Sky, colour of not mentioned in oldest 
books, 413 
Smith, Mr. Worthington, on mimicry 
in fungi, 397 
Smyth, Professor Piazzi, on the Great 
Pyramid, 430 
Snakes, mimicry among, 72 
characteristics of tropical, 304 
Sobralias, 256 
Soil, heat of, 222 
influence of temperature on cli- 
mate, 223 
Solenopsis, genus of ants, 281 
Song of birds, instinctive or imitative, 
104 
Sorby, Mr., on composition of chloro- 
phyll, 395 
Spalding, on instinctive actions of 
young birds, 109 
Sparrow learning song of linnet and 
goldfinch, 105 
Species, law of population of, 23 
abundance or rarity of, dependent 
on the adaptation to conditions, 
26 3 
diversity of opinions as to, 454 
Speed of animals, limits of, 160 
Sphecia craboniforme, 64 
Sphecomorpha chalybea, 68 
Sphegide, mimicked by flies, 69 
Spices from equatorial forest - trees, 
245 
Spiders, which mimic ants and flower 
buds, 70 
remarkable tropical, 291 
Spilosoma menthastri, 63 
Spruce, Dr. Richard, on habits of 
Indians of Peru, 107 
Spruce, Dr., on number of ferns at 
Tarapoto, 253 
on inconspicuousness of tropical 
flowers, 264 
Stainton, Mr., on moths rejected by 
turkeys, 56, 63 
Stalachtis, a genus of Erycinide, the 
object of mimicry, 60 
St. Helena, 9 
Stick-insects, 287 
Stinging insects generally conspicu- 
ously coloured, 52 
St. John, Mr., on large python, 305 
Stone mortars in auriferous gravels of 
Onlifornia, 445 
Streptolabis hispoides, 66 
Structure of humming-birds, 313 
Struggle for existence, 23, 25 
Sturnide, sexual colouring and nidifi- 
cation of, 127 
Sturnopastor, 123 
Sugar from palm-trees, 250 
Sun-birds, differences from humming- 
birds, 334 
Sun’s noonday altitude in Java and 
London compared, 221 
Sun’s rays, heating effect of, 221 
Sunrise in the equatorial zone, 233 
Survival of the fittest, law of, stated, 
26 
its action in determining colour, 
48 
Swainson’s circular and quinarian 
theory, 34 
Swallows, various forms of nests of, 
Swifts, resemblances of to humming- 
birds, 333 
and humming-birds, Dr. Shu- 
feldt on supposed affinities of, 
337 (note) 
Sylviade, sexual colouring and nidifi- 
cation of, 128 
Symmachia trochilus, 274 
colubris, 275 
Synapta, 136 
TacHORNIS phenicobea, 116 
Tanagride, sexual colouring and nidi- 
fication of, 127 
Tapir, ancestral types of, 165 
Telephori, similar colouring of two 
sexes, 80 
