212 ILLINOIS BIOLOGICAL MONOGRAPHS [500 



EXPLANATION OF PLATE 



Fig. 1. Ligula intestinalis, anterior end of larva, showing scolex. 



Fig. 2. Ligula inlestindis, anterior end of adult. 



Fig. 3. Schisiocephahis solidus, anterior end of larva. 



Fig. 4. Marsipometra hastata, scolex, surficial view. 



Fig. 5. Marsipometra hastata, same specimen, lateral view. 



Fig. 6. Bothrimonus intermedins, scolex, surficial view. 



Fig. 7. Bothrimonus intermedins, same specimen, lateral view. 



Fig. 8. Bothrimonus intermedins, same specimen, terminal view. 



Fig. 9. Baplobolhrinm globuJiforme, secondary scolex, surficial view. 



Fig. 10. Haplobothrium globuliforme, same specimen, lateral view. 



Fig. 11. Cyaihocephalus americanus, scolex, toto preparation. 



Fig. 12. Triaenophorus, larva, robustus ty-pe, surficial view. 



Fig. 13. Triaenophorus, same specimen, lateral view. 



Fig. 14. Triaenophorus, same specimen, one of the tridents of hooks. 



Fig. 15. Triaenophorus, larva, nodulosus type, surficial view. 



Fig. 16. Triaenophorus, same specimen, lateral view. 



Fig. 17. Triaenophorus, same specimen, a trident, terminal view. 



Fig. 18. Triaenophorus, same specimen, surficial view. 



Fig. 19. Bothriocephalus claviceps from Eupomotis gibbosus, scolex, surficial view. 



Fig. 20. Bothriocephalus claviceps, same specimen, lateral view. 



Fig. 21. Bothriocephalus scorpii, scolex, surficial view. 



Fig. 22. Bothriocephalus scorpii, same specimen, lateral view. 



Fig. 23. Bothriocephalus claviceps from Anguilla rostrata, scolex, surficial view. 



Fig. 24. Bothriocephalus cuspidatus, scolex, surficial view. 



Fig. 25. Bothriocephalus cuspidatus, same specimen, lateral view. 



Fig. 26. Bothriocephalus manubriformis, scolex, surficial view. 



Fig. 27. Bothriocephalus manubriformis, same specimen, lateral view. 



Fig. 28. Bothriocephalus occidentaUs, scolex. After Linton. 



Fig. 29. Clestobothrium crassiceps, scolex, surficial view. 



Fig. 30. Clestobothrium crassiceps, same specimen, lateral view. 



Fig. 31. Clestobothrium crassiceps, same specimen, terminal view. 



Fig. 32. Abothrium rugosum, scolex of young strobila. 



Fig. 33. A bothrium rugosum, later stage in degeneration of same. 



Fig. 34. Abothrium rugosum, still later stage. 



Fig. 35. Abothrium rugosum, pseudoscolex from lumen of pyloric coecum of host. 



Fig. 36. Abothrium rugosum, pseudoscolex from wall of coecum. 



Fig. 37. A bothrium crassum, scolex from Cristivomer namaycush. 



Fig, 38. Abothrium crassum, enlarged scolex from Lota maculosa. 



