WATER GRUB OF A MAY-FLY. 



139 



Dissection of the water-grub of a Msy-fly (Eyhtmria). TTie back 

 is laid open, and the neirrs, intestines, and rcs!>imtory apparatua 

 exhibited, aanann. six clii:?lers of short tubes, opening on both 

 sides, through which the ere itiir<- breathes: t!ie air contained in the 

 water, passing throueli these, enters two wiud-pipcs, '; h b ft, running 

 from head to tail, and circ'-:l:iies hrough every part of the body, 'ihe 

 eight fins, and a portion of the tiiil bristlrshive been omitted, to give 

 the rest of lh«' figure on a l.ircer scale. The cpntr.nl while linra are 

 the nerve*. 



