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five carpels, whose bases are more or less sunk in the sub- 

 stance of the tube. When fruit forms the tube grows enor- 

 mously, carrying up the withered sepals on its apex, and 

 burying the carpels in its centre. If you cut an apple 

 through, the outer part of its flesh was formed from the 

 tube, and the inner portion and the hard part of the core 

 from the carpels, in each of which are one or two pips or 

 seeds. 



We have two native Raspberries, and a very much run 

 wild Bramble or Blackberry. They develop another form 

 of fruit. The floral tube is small, but the centre of the 

 thalamus grows into a cone, upon which are placed few or 

 many carpels. The fruit is formed by each carpel growing 

 into a small fleshy globe with a hard centre containing 

 a seed. The cone of the thalamus grows to accommodate 

 the enlarged carpels. 



The Strawberry is a further modification of this. The 

 central portion of the thalamus enlarges into a great fleshy 

 fruit carrying the little dry carpels on its surface 



It is unusual for a family of plants to have so much 

 variation in the structure of its fruit as we find in the 

 Rose familv, but we must be always prepared to meet 

 great diversity ; not only that, but we must not be sur- 

 prised if we find such a fruit as a berry in many different 

 families. We find the immediate organs of reproduction 

 are altered only slightly in long periods of time. Their 

 position on the plant may be subject to modification, but 

 their characters are ever the same. There is little differ- 

 ence in the pollen sacks of the anthers and the ovum sacks 

 of the ovules throughout the whole range of flowering 

 plants. And they do not materially differ from the same 

 organs found in lower plants. Their function is definite 

 and their character fixed. With fruits it is a very different 

 matter. Their function is to protect and disseminate the 

 seeds in the most effective manner. We find some fruits so 

 hardened that neither animals nor fire can damage the 

 seed; others open elastically, and cast the seed far away; 

 others again are winged, to ensure being blown to new 

 places ; while yet others tempt animals to eat them and 

 cast the undigested seed in new situations. Any advan- 

 tageous change is of great benefit, as it enables a plant 

 to propagate more effectively than its fellows. Wherefore 

 if a plant develops a small but effective improvement, and 

 such sudden developments take place oftener than is 

 generally supposed, it will have an advantage which will 

 enable it to spread more effectively than the others of its 



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