V. Volitores.

Birds moving solely by flight. Skeleton light and buoyant; head large; keel deep (entire on the Humming-bird); wings powerful, in some long and pointed; legs small and weak. The order includes—

I. Cypselidæ, Swifts.

II. Trochilidæ, Humming-birds.

III. Caprimulgidæ, Night-jar.

IV. Trogonidæ, Trogons.

V. Prionitidæ, Momots or Motmots.

VI. Meropidæ, Bee-eaters.

VII. Galbulidæ, Jacmar.

VIII. Coraciadæ, Rollers.

IX. Capitonidæ, Puff-bird.

X. Alcedinidæ, King-fishers.

XI. Bucerotidæ, Hornbills.