U. S. NATIONAL MUSEUM 



266 



PROCEEDINGS, VOL. 88 PLATE 20 



270. 



266,167. Steringophorus furciger (Olsson) from Pseudopleuronectes amencanus: 266, Sagittal 

 section, anterior end; 267, frontal section. _ 



268-271. Lintonium vihex (Linton) from Sphoeroides maculatus: 268, Dorsal view; IW, 

 sagittal section, anterior end; 270, sagittal section showing Laurer s canal; 271, 

 immature specimen, ventral view. (In some cases the intestines were entirely 

 ventral to the excretory vessels.) 



