ABT. 21. PAEASITES OF SHARKS AND SKATES LINTON. 109 



Phoreiobothrium exceptum, new species, from Cestracion zygaena. 



Fig. 41. Scolex and anterior part of strobile ; balsam ; diameter of scolex 0.56. 



42. Eothrium ; balsam ; length 0.47. 



43. Pair of hooks ; maximum length 0.13. 



44. Spines from neck ; maximum length 0.036. 



Plate 5. 



Phoreiobothrium triloculatum Linton, from Carcharhinus obscurus. 



Fig. 45. Bothrium ; balsam ; length 0.60. 



46. Pair of hooks; maximum length 0.15. (a) Spines from neck; maxi- 

 mum length 0.012. 



Phoreiobothrium pectinatum, new species, from Cestracion zygaena. 



Fig. 47. Bothrium ; balsam ; length 0.18. 



48. Pair of hooks ; maximum length 0.06. 



49. Spines from neck ; maximum length 0.03. 



50. Proglottis ; balsam ; length 1.22. 



Platybothrium cervimim Linton, from Carcharhinus obscurus. 



Fig. 51. Scolex; balsam: breadth 0.52. (a) Spines from neck; maximum 

 length 0.015. 



Platybothrium. parvum Linton, from Cestracion sygaena. 



Fig. 52. Scolex ; flattened under cover glas.s, and fixed over flame ; breadth 0.35. 

 53. Proglottis ; balsam ; length 2.10. 



Phoreiobothrium. lasium Linton, from Carcharhinus obscurus (see fig. 36-40). 



Fig. 54. Segmenting ova ; length of smallest, 0.06. 



Plate 6. 



Ichthiotaenia adherens, new species, from Cestracion zygaena. 



Fig. 55. Scolex ; balsam ; diameter 0.45. 



56. Anterior end of ripe proglottis with wall ruptured exposing the uterus 



filled with, large, segmenting ova ; breadth, in front of genital 

 pore, 1.68. 



57. Part of transverse section of immature proglottis near genital pore; 



two sections used ; diameter of section at median line 0.5. 



58. Spine from cirrus ; length about 0.008. 



59. Part of transverse section near posterior end of immature proglottis; 



diameter at median line 0.5. 



Plate 7. 

 Otobothrium penetrans Linton, from Cestracion xygoena. 



Fig. 60. Strobile ; alcohol ; length 122. 



61. Scolex and anterior part of stobile ; balsam ; length of scolex 4.5. 



62. Proboscis, near base ; diameter 0.21. 



63. Proboscis, middle; diameter 0.18. 



64. Hooks from near base of proboscis, drawn to same scale ; maximum 



length 0.11. 



65. Immature proglottides ; length of single proglottis 1.26. 



66. Ripe proglottides ; balsam ; length of longest 8. 



67. Ripe proglottis ; balsam : lengtli 5. 



