210 



S. STILLMAN BERRY. 



In the present form they are quite small. A little behind the 

 middle of the body is a very conspicuous transverse series of 

 five organs. The central one is unpaired. Close to it on each 



FIG. i. 



side is a very large flattened organ. The terminal organs are 

 the smallest of the series and -situated one at the base of each 



