WATER GRUB OF A MAY-FLY. 



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Dissection of the water-grub of a May-fly (Ephemera). The back 

 is laid open, and the nerves, intestines, and respiratory apparatus 

 exhibited, aaaaaa, six clusters of short tubes, opening on both 

 sides, through which the creature breathes: the air contained in the 

 water, passing through these, enters two wind-pipes, bhb b, running 

 from head to tail, and circulates through every part of the body. The 

 eight flns, and a portion of the tail bristles have been omitted, to give 

 the rest of the figure on a larger scale. The central white lines are 

 the nerves. 



