on understanding of words by brutes, [127];
on roots of language, [268], [273], [336];
on distinction between ideas as general and generic, [279];
on increasing conceptuality of terms with increase of culture, [280];
on the impossibility of language having ever consisted exclusively of general terms, [282];
on Heyse’s theory of the origin of speech, [289];
on onomatopœia, [292];
on the vanishing point of language, [314], [354];
on fundamental metaphor as illustrated by names of tools, [345], [346],