326 ILLINOIS BIOLOGICAL MONOGRAPHS [326 



EXPLANATION OF PLATE 



Fig. 47. — Proteocephalus macro cephalus (Creplin), ripe proglottid showing fe- 

 male reproductive organs. From Sebago Lake material. 



Fig. 48. — Proteocephalus macro cephalus (Creplin), ripe proglottid, cross-sec- 

 tion in region of cirrus-pouch. Partial reconstruction. From Sebago Lake 

 material. 



Fig. 49. — Proteocephalus macrocephalus (Creplin), ripe proglottid showing 

 male organs. From Sebago Lake material. 



Fig. 50. — Proteocephalus exiguus La Rue, mature proglottid, toto. 



Fig. 51. — Proteocephalus exiguus La Rue, end-proglottid, ventral view of toto 

 preparation. Note the excretory pore and the shape of the ovary. 



Fig. 52. — Proteocephalus exiguus La Rue, ripe proglottid, toto, as seen from 

 dorsal side, testes omitted. 



Fig. 53. — Proteocephalus pusillus Ward, ripe proglottid, toto, showing uterine 

 pouches and a rare abnormality in the position of the vagina which is here poste- 

 rior to the cirrus-pouch. From Salmo sebago. 



Fig. 54. — Proteocephalus pusillus Ward, mature proglottid, toto. From Salmo 

 sebago. 



Fig. 55. — Proteocephalus pusillus Ward, mature proglottid, toto, showing male 

 reproductive organs and the usual relation of vagina and cirrus-pouch. From 

 Cristivomer namaycush. 



Fig. 56. — Proteocephalus fallax La Rue, ripe proglottid, toto. Shows two ven- 

 tral uterine pores. This figure is inverted. 



Fig. 57. — Proteocephalus fallax La Rue, mature proglottid, toto, ventral view. 

 Note musculature of cirrus-pouch. 



