216 ILLINOIS BIOLOGICAL MONOGRAPHS [504 



EXPLANATION OF PLATE 



Fig. 45. Bothrimonus intermedins, scolex and anterior end, toto preparation, showing fore- 

 most sets of genitalia. 



Fig. 46. Marsipometra hastata, plerocercoid, surficial view. 



Fig. 47. Marsipometra hastata, older plerocercoid, surficial view. 



Fig. 48. Clestobothrium crassiceps, toto of scolex and anterior end. 



Fig. 49. Clestobothrium crassiceps, toto of young strobila, surficial vi ew. 



Fig. 50. A bothrium crassiim, plerocercoid from Cristivomer namaycush, surficial view. 



Fig. 51. Abothrium crassum, same specimen, lateral view. 



Fig. 52. Abothrium crassum, yoimg strobila from same host. 



Fig. 53. Abothrium crassum, older strobila from same host. 



Fig. 54. Abothrium crassum, still older strobila, showing dropping off of segments posteriorly. 



