110 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.64. 



Fig. 68. Sagittal section of ripe proglottis ; length 1.S2. 



69. Median region of transverse section of adult proglottis ; diameter of 



section 0.26. 



70. Diagrammatic plan of gential ducts in vicinity of shell gland, o. d. 



oviduct. 



Rhynchobothrium, species, from Narcadon nohilianus. 



Figs. 71, 72. Views of proboscis ; diameter, excluding hooks, 0.03. 

 73. Hooks ; maximum length 0.036 ram. 



Rhynchobothrimn uncinatum, new species, from Vulpecula marina. 



Fig. 74. View of mid- region of proboscis; length of hooks 0.05 (see figs. 

 7.5-78). 



Plate 8. 



Rhynchobothrium uncinatum, new species, from Vulpecula marina (see fig. 74). 



Fig. 75. Scolex ; balsam ; breadth through bothria 1.12. 



76, 77. Views of opposite sides of the base of a proboscis, small hooks 

 somewhat diagrammatic ; diameter in region of small hooks 0.075. 

 78. Posterior proglottis ; length 3.91. 



Tetrarhynchus bicolor Bartels, from Carcharhinus obscurus. 



Fig. 79. Scolex ; life ; length 10.5. 



80. Scolex with proboscides everted ; life ; length 8.5. 



Tetrahynchus palUatus, new species, from Cestracion zyga^na. 



81. Scolex; balsam; length 3.82. 



82. View of proboscis ; diameter, including hooks, 0.05. 



83. 84. Sagittal sections of a proglottis ; length 0.56. 



Plate 9. 



Rhynchobothrium exile Linton, from Oaleocerdo arcticus. 



Fig. 85. Scolex ; balsam ; length 2.52. 



86, 87. Views of opposite sides of base of a proboscis. 



88. Probocls, above base ; diameter, excluding hooks, 0.03. 



89. Hooks of same. 



90. Posterior, but still immature proglottis ; balsam ; length 2.60. 



Rhynchobothrium, species, near R. temispitie from Dasybatis Centura. 



Fig. 91. Scolex and small portion of strobile ; balsam ; length of scolex 1.06. 

 92. Base of proboscis. 

 98, 94. Views of other regions of proboscis ; diameter, including hooks, 0.015. 



Plate 10. 

 Synbothrium malleum, new species, from Dasybatis Centura. 



Fig. 95. Hooks from proboscis ; length of smallest 0.015; length of longest O.Ol). 



96. Hooks from proboscis of another specimen, drawn to same scale as 



fig. 95. 



97. Posterior proglottis ; balsam ; length 2.34. 



98. Transverse section near anterior end of proglottis, passing through 



the point where the uterus opens to the exterior; longest diameter 

 of section 1.23. 



