Group Cirro-stratus.
Under this group the cloud usually shows some structure, being apparently built up from a massing together of detached forms at a common level. When this is so it should be described by adding the specific name of the detached form most nearly related.
1. Cirro-stratus nebulosus (Plates [3], [4], and [14]). Hazy cirro-stratus.
Characterized by absence of visible structure. Ci. S. Neb.
2. Cirro-stratus communis (Plate [16]). Common cirro-stratus.
Characterized by the presence of short curling fibres matted together. Ci. S. Com.
3. Cirro-stratus vittatus (Plate [57]). Ribboned cirro-stratus.
Characterized by being made up of long stripes or bands of cloud. Ci. S. Vt.
4. Cirro-stratus cumulosus (Plate [17]). Flocculent cirro-stratus.
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.