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The Museum Gazette 



grows downwards in the leaf stalk, and forms a separating 

 layer, a " line of demarcation," through still living tissue. 

 This eventually causes the leaf to be held in position only by 

 the vascular tissue. A slight breeze at once causes the leaf 

 to fall, its own weight is often sufficient to bring about the 

 result, and certainly frost accelerates it. The scar is quickly 

 covered with a corky layer, or sealed with a sticky fluid. 



The process of exfoliation may be well observed in the 

 leaves of the horse chestnut and walnut, those of the beech 

 also show it very well. Of course, a microscope is essential. 



QUESTIONS FOR ANSWERS. 



[Continued from p. 116.) 



(11) Who were " Mrs. Morley " and " Mrs. Freeman " ? 



(12) Some authorities suppose that the book of Job was 

 written by Solomon, or one of his contemporaries. If this 

 were so, what would be its relation in point of time to the 

 Christian era ? 



(13) The world on which we live is believed to be round, 

 and to be one of several somewhat similar globes, which are 

 arranged in orbits round the sun, and are known as " planets." 

 Give the names which have been bestowed on the other 

 " planets," and state which are larger and which smaller than 

 the earth. 



(14) What is the measured distance of the planet earth 

 from the centre of the solar system ? 



(15) In the language of the zoologist and botanist, what is 

 £he meaning of the word "cell"? Is it used in the same 

 sense in which we speak of a " prison cell " or a " hermit's 

 cell " ? 



(16) Give the meanings of the words lumen, foramen, bulla, 

 verruca, trabecula, when used in Nature-study. 



