371] 



XORTII AMERICAN POLYSTOMIDAE—STl r NKARD 



91 



EXPLANATION OF PLATES 



All figures except those of reconstruction were drawn with the aid of a 

 camera lucida and were made from permanent mounts. 



Abbreviations used 

 acetabulum 

 esophageal bulb 

 circular muscles 

 cirrus sac 



a 



b 



cm 



cs 



e 



ed 



ep 



9P 



gc 



h 



hd 



i 



I 



Im 



Is 



It 



in 



md 



mg 



mo 



nit 



mv 



esophagus 



excretory duct 



excretory pore 



genital pore 



genito-intestinal canal 



small hooklets 



hermaphroditic duct 



intestine 



Laurer's canal 



longitudinal muscles 



lymph sinus 



limiting membrane 



mouth 



median dorsa! lymph canal 



Mehlis' gland 



marginal organ 



metraterm 



median ventral lymph canal 



nc nerve commissure 



o ovary 



oc eye spot 



od oviduct 



om oblique muscles 



oo ootype 



op oral evagination 



os oral sucker 



ov egg 



p postate gland 



ph pharynx 



sp septum 



sv seminal vesicle 



t testis 



n uterus 



nd uterine duct 



v vitellaria 



vd vas deferens 



vg vagina 



vl vitelline duct 



vv vitello-vaginal canal 



