96 CEYLON PEART, OYSTER REPORT. 



Fig. 104. Phi/llobothriiim luctuca, VAN BEN. x 2. a., outline of proglottides about middle of body ; 



/>., the same from posterior part of body. 



105. Head of Pltyllohothriuin lactuca. x 6. 



,, 106. Tetrarhynchus equidentatus. x 4. 



107. Proboscis of the same, x 50. 



108. Tetrarhynchus herdmani. x 6. 



109. The head of the same, x 60. 



110. Tetrarhynchm macrocephalus. x 10. 



111. View of the concave side of a proboscis of the same. 



112. View of the convex side of a proboscis of the same. 



113. Tetrarhynchus platijcephalus. x 10. 



114. Head of the same, x 45. 



115. Tetrarhynchm mbromaculatus (DiESiNG). x 40. a., a further enlarged view of the end of 



a proboscis. 



116. Tetrarhynchm ruficollis (EvSENH.). x 6. 



,, 117. Head of the same, x 12. a., further enlarged view of the end of a proboscis. 



118. Tetrarhynchus unionifactw, x about 100, from alimentary canal of pearl oyster. 



