An inauspicious bird also is that known as the “incendiary;”[2940] on account of which, we find in the Annals, the City has had to be repeatedly purified; as, for instance, in the consulship of L. Cassius and C. Marius,[2941] in which year also it was purified, in consequence of a horned owl being seen. What kind of bird this incendiary bird was, we do not find stated, nor is it known by tradition. Some persons explain the term this way; they say that the name “incendiary” was applied to every bird that was seen carrying a burning coal from the pyre, or altar; while others, again, call such a bird a “spinturnix”;[2942] though I never yet found any person who said that he knew what kind of bird this spinturnix was. (14.) I find also that the people of our time are ignorant what bird it was that was called by the ancients a “clivia.” Some persons say that it was a clamatory, others, again, that it was a prohibitory, bird. We also find a bird mentioned by Nigidius as the “subis,” which breaks the eggs of the eagle. (15.) In addition to the above, there are many other kinds that are described in the Etruscan ritual, but which no one now living has ever seen. It is surprising that these birds are no longer in existence, since we find that even those kinds abound, among which the gluttony of man commits such ravages. CHAP. 18. (16.)—BIRDS WHICH ARE BORN WITH THE TAIL FIRST. Among foreigners, a person called Hylas is thought to have written the best treatise on the subject of augury. He informs us that the owlet, the horned owl, the woodpecker, which makes holes in trees, the trygon, and the crow, are produced from the egg with the tail[2943] first; for the egg, being turned upside down through the weight of the head of the chick, presents the wrong end to be warmed by the mother as she sits upon it. CHAP. 19. (17.)—THE OWLET. The owlet shows considerable shrewdness in its engagements with other birds; for when surrounded by too great a number, it throws itself on its back, and so, resisting with its feet, and rolling up its body into a mass, defends itself with the beak and talons; until the hawk, attracted by a certain natural affinity, comes to its assistance, and takes its share in the combat. Nigidius says, that the incubation of the owlet lasts sixty days, during the winter, and that it has nine different notes. CHAP. 20. (18.)—THE WOOD-PECKER OF MARS.