The natives say that, if a drop falls into the eyes, it causes inflammation of these organs.

To the question whence is this fluid derived, the people reply that the insects suck it out of the tree, and our own naturalists give the same answer.

I have never seen an orifice, and it is scarcely possible that the tree can yield so much.

A similar but much smaller homopterous insect, of the family 'Cercopidae', is known in England as the frog-hopper ('Aphrophora spumaria'), when full grown and furnished with wings, but while still in the pupa state it is called "Cuckoo-spit", from the mass of froth in which it envelops itself.
The circulation of sap in plants in our climate, especially of the graminaceae, is not quick enough to yield much moisture.

The African species is five or six times the size of the English.