11. Layer of Stratocumulus, L„. 



This layer is in rather irregular waves or rolls, with lighter semi- 

 transparent parts. Occasionally stratocumulus appears in rolls which 

 are very symmetrically arranged; usually the layer is more or less 

 broken. These clouds are not formed from cumulus; otherwise they 

 would be coded X4. (Photo at Washington, D. C, by W. J. Hum- 

 phreys.) 



12. Layer of Stratocumulus, L5. 



These clouds show dark shadows but large patches of sky may be 

 seen between them. This layer is called stratocumulus. However, 

 the photograph was taken on Mount Wilson at a height of 1,750 

 meters. Had the observer been at sea level the clouds would have 

 appeared smaller and might have been called altocumulus or high 

 stratocumulus, requiring code M^. (Photo by F. Ellerman.) 



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