begins to show results. With this constant strain on the 

 adductor muscle of the bivalve, which is in a state of con- 

 tinuous contraction, fatigue soon becomes apparent until 

 at last in utter exhaustion the valves slowly open, when the 

 first act in this tragedy of the ocean floor is closed. This 

 silent executioner has his intended prey helpless, shell agap, 

 yet the delicious morsel seems beyond his reach. How will he 

 surmount this apparently insuperable barrier? The final act 

 in the tragedy is ushered in by a wonderful phenomenon, 

 now the significance of the position first taken by the star- 

 fish becomes apparent, its mouth is opposite the partially 

 opened edges of the shell, and at once there begins a gradual 

 eversion of the star's stomach, which commences to roll out 

 of its mouth, and is pushed by vermicular motion between 

 the edges of the valves, to enter the body of the mollusk 

 in the form of a membrane which spreads over the soft 

 tissues of the victims body. What is normally the inner 

 layer of mucous membrane of the star's stomach, when in- 

 verted, becomes the outer layer for the time being, and in 

 close touch with the living banquet. Then from the numer- 

 ous glands of this mucous layer of the star's stomach is 

 poured out a generous quantity of one of the most powerful 

 digestants known. With man, food in order to be made ready 

 for assimilation must be masticated and thoroughly mixed 

 with tyalin from the sublingual glands in the mouth before 

 entering the stomach. Thus the process of digestion is be- 

 gun, the tyalin changes the starches of the food into dex- 

 trose even before it is swallowed. The food after entering 

 the stomach is acted upon by the gastric juices and acids of 

 the stomach which carry on the process of digestion a step 

 farther, when the partially digested food enters the intestine 

 where other ferments are added to complete the process of 

 digestion. 



The common housefly lays its eggs when convenient in 

 dark moist crevices, in meat, or flsh, at the same time it 

 deposits in the vicinity of the eggs a strong digestant that 

 soon begins to liquify the flesh, in order that when the larvae 

 are hatched that they may have a semi-liquid predigested 

 food as a medium to wiggle about in and absorb through 

 the delicate skin with which they are covered. 



In the case of man the food is cooked to render it more 

 easily digested and is digested only after it has been masti- 

 cated and taken into the stomach. With the fly the food 

 may be uncooked but not endowed with life and is digested 

 outside the fly's body. This fact would indicate that a much 

 stronger aid to digestion was used in case of the fly than 



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