Child, mental development of, [204]
Christianity, [192], [250], [252]
Church, [265]
Circulatory system, worms, [62]; insects, [66]; vertebrates, [84]
Classification, [20]
Conformity to environment, [150], [170], [177], [197], [243], [259], [265]
Conscience, [184]
Correlation of organs, [284]
Darwinism, [10]