Friese, on habits and classification of bees, [21];

on hosts and parasites, [30] f.

Fritillaries, [352], [354]

Froghoppers, [577]

Frog-spit, [577]

Frontal ganglion, [320]

Fulgora candelaria, [575]

Fulgoridae, [543], [574];

larva living on, [404]

Fulgorina, [543]