RELATIONS OF RHABDOPLEURA. 



583 



Schematic and hypothetical diagram of Rhabdopleura. a. Lophophore, with 

 origin of tentacles ; h. Shield ; c. Mouth ; d. CEsophagus ; e. Stomach ; /. In- 

 testine ; g. Anal orifice ; h h. Endocyst ; i. Contractile cord ; k. Commence- 

 ment of the chitinous rod ; External chitinous tube. 



The representative of the endocyst is indicated by the broad dark line. 



