212 ILLINOIS BIOLOGICAL MONOGRAPHS [500 



EXPLANATION OF PLATE 



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



Fig. 2. Ligtila intestinalis, anterior end of adult. 



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



Fig. 4. Marsipomeira haslata, scolex, surficial view. 



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



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



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



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



Fig. 9. Haplobolhrium glohuliforme, secondary scolex, surficial view. 



Fig. 10. Haplohothrium glohuliforme, same specimen, lateral view. 



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



Fig. 12. Triaenophorus, larva, robustus type, surficial view. 



Fig. 13. Triaenophorus, same specimen, lateral ^^ew. 



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



Fig. 15. Triaenophorus, larva, nodidosus 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 gibhosus, 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 occidentalis, 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. Abothrium rugosum, later stage in degeneration of same. 



Fig. 34. Abothrium rugosum, still later stage. 



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



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



Fig. 37. Abothrium crass7im, scolex from Cristivomer namaycush. 



Fig. 38. A botkrium crassum, enlarged scolex from Lota macidosa. 



