PLANAEIEA. 



79 



lengthened and flattened, but not divided into 

 segments ; furnished with organs of sense (eyes) , 

 and either sexless or with the sexes united in the 

 same individual. 



Body flattened, not greatly longer than 

 broad, without trace of divisions or segments Plcmariea. 



Body roundish, linear, greatly lengthened, 

 indistinctly ringed Cestoidea. 



121 



125 



127 



12S 



129 



130 



132 



Order I. PLANAEIEA. 



Intestine branched : 



Mouth very large, almost plane, free 

 in a proper cavity, opening near the 

 middle of the belly ; eyes in groups . Cryptoccela. 



Mouth small, cylindrical, free in a 

 cavity, very protrusile Dendrocasla. 



Intestine simple Rhabdoccela. 



