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PROCEEDINGS OF THE NATIONAL MUSEUM 







Figure S. — a, Aquaplana pacifica, sagittal view of copulatory apparatuses, male apparatus 

 to right; b-d, Paraplanocera fritillata: b, entire animal; c, eyes and tentacles enlarged; 

 d, copulatory region as seen from ventral side in cleared animal. (Explanation on page 

 597.) 



