Mammæ, rudimentary, [451].

Mammals, fossil, in secondary formation, [304].

——, insular, [394].

Man, origin of races of, [199].

Manatee, rudimentary nails of, [454].

Marsupials of Australia, [116].

——, fossil species of, [339].

Martens, M., experiment on seeds, [360].

Martin, Mr. W. C., on striped mules, [165].

Matteucci on the electric organs of rays, [193].