These features are common to all types of cumuloform clouds. Cirrostratus are high clouds that usually blanket the sky in ill-defined sheets. These clouds are usually optically thin and the sun and moon can usually shine some light through. Like other stratiform clouds, one usually can't detect distinct cells or sharp features. This picture shows the sun shining through a gray, diffuse cirrostratus overcast.
Middle clouds have many similarities to the cumuloform and stratiform high clouds.
Since they are closer to a groundbased observer, the cumuloform elements in particular appear larger than their high cloud counterparts. Altocumulus have distinct cloud elements and are either in a patchy, scattered distribution or can appear in linear bands. The altocumulus in this photo by Jay Shafer consists of a number of individual cloud elements. Jay also took this beautiful sunset photo of altocumulus clouds. Altostratus have a more uniform and diffuse coverage where it is difficult to detect individual elements or features.