As to the quotations, it is difficult to say precisely which species of hirundo Virgil might intend in the lines in question, since the ancients did not attend to specific differences like modern naturalists: yet somewhat may be gathered, enough to incline me to suppose that in the two passages quoted the poet had his eye on the swallow.
In the first place the epithet garrula suits the swallow well, who is a great songster; but not the martin, which is rather a mute bird; and when it sings is so inward as scarce to be heard. Besides, if tignum in that place signifies a rafter rather than a beam, as it seems to me to do, then I think it must be the swallow that is alluded to, and not the martin; since the former does frequently build within the roof against the rafters; while the latter always, as far as I have been able to observe, builds without the roof against eaves and cornices.
As to the simile, too much stress must not be laid on it: yet the epithet nigra speaks plainly in favour of the swallow, whose back and wings are very black; while the rump of the martin is milk- white, its back and wings blue, and all its under part white as snow. Nor can the clumsy motions (comparatively clumsy) of the martin well represent the sudden and artful evolutions and quick turns which Juturna gave to her brother's chariot, so as to elude the eager pursuit of the enraged Aeneas. The verb sonat also seems to imply a bird that is somewhat loquacious.* (* Nigra velut magnas domini cum divitis aedes Pervolat, et pennis alta atria lustrat hirundo, Pabula parva legens, nidisque loquacibus escas: Et nunc porticibus vacuis, nunc humida circum Stagna s
