8 Papers from the Marine Biological Laboratory at Tortugas. 



i. The whole worm viewed from ventral side: actual length 1.3 mm. 



2. Dorsal surface of anterior portion of worm: X 25. 



3. Sagittal section of anterior portion of worm: X 18. 



4. Dorsal view of posterior portion of worm: X 20. 



5. Longitudinal section of sucking-disk and peduncle: X 40. 



6. Section of outer portion and flange of a sucker : X 200. 



7. Hook in sucking-disk: X 150. 



8. Diagram showing arrangement of reproductive organs. 



