43. Cirrus of Anvil Clouds, H3. 



The cirrus clouds in this picture are c{uite dense in phices. The 

 wisps of "spindrift" at the upper left are characteristic of a thundery 

 tendency. Although the anvil shape is completely lost, these clouds 

 were probably derived from cumulonimbus clouds at some consider- 

 able time preceding the taking of this picture. (Photo taken at 

 Ebro Observatory, Tortosa, Spain.) 



44. Cirrus of Anvil Clouds, Hi. 



In this picture the typical anvil is seen, composed entirely of dense 

 cirrus, frayed out at the upper left. There are cumulus clouds below 

 with the cirrus of another anvil in the distance at the right. The 

 cumuliform parts of the main cumulonimbus have degenerated. Tliis 

 is a transitional stage between Z3 and Hi- (Photo at Cheyenne, Wyo., 

 by H. T. Floreen.) 



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