tal and Siberian mammals from, 176, 206
during Glacial period, 176

Scandinavian boulders, origin of, 172-173
butterflies in America, 167
flora, antiquity of, 162, 185
glaciers, 172

Scandinavian lepidopterous fauna, 55

Schulz, A., 52, 155

Sclater, P. L., 95

Scotch Argus, 325

Scotch and Irish Hare, 136

Siberia, climate of, during Glacial period, 217

Siberian birds in British Islands, 191-192
mammals absent from Scandinavia, 176, 206
mammals absent from Southern Europe, 206
mammals in Great Britain, 95-96, 190, 202-204
migration, date of, 208
steppe-fauna, 39

Sicily, Pliocene deposits in, 277

_Silurus glanis_, 29

Simpson, C. T., 21

Simroth, H., 48, 299

Sjoegren, H., 226

Slugs, dispersal of, 16-17

Snails, dispersal of, 17

Snow-Bunting, range of, 91, 140

Snow-Finch, 318

Sollas, W., 177

_Somateria mollissima_, 141

_Sorex_, 202, 314-315
_alpinus_, 314-315
_araneus_, 315
_minutus_, 315

Southern mammals in Arctic Siberia, 213-216

Sparrow, introduction of, 28

_Spermophilus_, 41

Speyer, A. and A., 55, 200

Spiders, Lusitanian, 301

Sponges, American, in Ireland, 166

St. Erth fauna, 174

Steinbock, 312

Steppe-fauna, Siberian, 39

Sterlet, introduction of, 29

Stick-insect, 269

Stickleback, origin of, 92, 143, 166-167

Stoat, range of, 90-91, 135-136

Straits of Gibraltar, age of, 277-278, 281

_Strix flammea_, 98

_Strongylocentrotus lividus_, 125

Struckmann, C., 153

Studer, Th., 340

Sub-marine plateau between Norway and Spitsbergen, 154

Suess, E., 61, 273, 282, 303

_Sus scrofa_, 44-46

Swallow-tail Butterfly, 264-265

_Syrrhaptes paradoxus_, 41, 205

Tailless Hare, 41

_Talpa_, 291

Taylor, J. W., 105

Tcherski, J. D., 214-215, 222

Tertiary plants in Greenland, 144-145

_Testacella_, 17, 299
_haliotidea_, 299
_maugei_, 102, 299
_scutulum_, 299

_Tetrao_, 28
_urogallus_, 28, 143, 336-337

_Tetrastes bonasia_, 337

_Tettix_, 330
_bipunctatus_, 330

_Thais cerisyi_, 265

_Thelphusa fluviatilis_, 270, 281

Thomas, O., 90

Thompson, W., 32

Time of disconnection between Great Britain and Ireland, 63

Titmouse, bearded, 292

Toad, Natterjack, 30

Tree-frog, 260, 280

_Trichomanes radicans_, 115

_Tropidonotus vi