Characterized by an obscurely granular structure. Ci. S. Cu.

Many forms of cirro-stratus are arranged in waves or ripples. This is indicated by attaching the word undatus, or waved, after the ordinary specific name, or the letter U after the abbreviation.

Group Cirro-cumulus. Divisible into three species.

1. Cirro-macula (Ley) (Plate [23]). Speckle cloud.

Characterized by semi-transparency, by the fact that the particles are frequently whiter and more opaque on their edges. A patch of cirro-macula always looks like a thin sheet which has curdled. Ci. Ma.

2. Cirro-cumulus nebulosus (Plates [20] and [21]). Hazy cirro-cumulus.

Characterized as rounded balls of semi-transparent cloud, but ill-defined and hazy. No shadows. Ci. Cu. Neb.

3. Cirro-cumulus (Plates [18] and [19]).

Characterized as opaque rounded balls clearly defined, but showing no shadows on their under sides. Ci. Cu. Com.