Thomson, Sir William, [136].

Thoracic fishes, [39].

Thorax of crustaceans, [79].

Thylacine, [67].

Tierra del Fuego, [192].

Tiger, sabre-toothed, [110].

Time required for evolution, [128].

Tope, [172].

Trabeculæ cranii, [172].

Transitional forms, [128].