WATER-GRUB OF A MAY-FLY 



Dissection of the water-ffrub of a May-liy {Epficmera). 'I'he 

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

 apparatus exhibited, a a a a a a, six clnster.s of short tub-s. 

 opening on both sides, througli which the creature breathes: the 

 air contained in the water, jjissiiig through these, enttrs twcr 

 wind-pipes, h b b b, rnniuug from head to tail, and circulates 

 through every part of the boily. The eiffht tins, ami a portinu of 

 the tail-bristles have been omitted, to give the rest of the figure 

 on a larger scale. The central white .ines arc the nerveb. 



