The Spanish Copris: the Mother 



attracts attention by its size, but it grows 

 much larger before hatching, increasing two- 

 or threefold in bulk. Its moist chamber, 

 saturated with the emanations from the 

 provisions, supplies it with nourishment. 

 Through the chalky porous shell of the 

 bird's egg, an exchange of gases takes place, 

 a respiratory process which quickens matter 

 while consuming it. This is a cause of de- 

 struction as well as of life: the sum total of 

 the contents does not increase under the in- 

 flexible wrapper; on the contrary, it 

 diminishes. 



Things happen otherwise in the Copris' 

 egg, as in the other Dung-beetles'. We 

 still, no doubt, find the vivifying assistance 

 of the air; but there is also an accession of 

 new materials which come to add to the re- 

 serves furnished by the ovary. Endosmosis 

 causes the exhalations of the chamber to 

 penetrate through a very delicate membrane, 

 so much so that the egg is fed, swells and 

 enlarges to thrice its original volume. If we 

 have failed to follow this progressive growth 

 attentively, we are quite surprised at the 

 extraordinary final size, which is out of all 

 proportion to that of the mother. 



This nourishment lasts a fairly long time, 

 for the hatching takes from fifteen to twenty 



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