Rohfs, Dr., Caucasian features in negro; fertility of mixed races in Sahara; colours of birds in Sahara; ideas of beauty amongst the Bornuans.
Rolle, F., on the origin of man; on a change in German families settled in Georgia.
Roller, harsh cry of.
Romans, ancient, gladiatorial exhibitions of the.
Rook, voice of the.
Rossler, Dr., on the resemblance of the lower surface of butterflies to the bark of trees.
Rostrum, sexual difference in the length of in some weevils.
Royer, Madlle., mammals giving suck.
Rudimentary organs, origin of.
Rudiments, presence of, in languages.