247 



U 



Fig. 193. — Ulmaris prototf/pus. (From Hatschek ) 7, radii of first order (perradii); 

 II, radii of second order (interradii): I, mart=rinal lobes; o oral lobes (cut away on 

 right side); (, tentacles (adradial); the gonads (right side) are interradial. 



Fig. IQi.—PolycIonia frondof;n* an(\ onn of its branchine oral lobes, ^^liuwiiiLi; the 

 closed (grooves (.si. (After Agassiz I 



