886 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [168] 



PLATE X. 

 Discocephalum pileatum, gen. et sp. nov. 



FIG. 1. Var. a. Head and neck, from life, X 9. 



FIG. 2. Var. (3. Head aiidjieck of living specimen, X 9. 



FIG. 3. Another view of the same, X 9. 



FIG. 4. Outline of median segments, from life, X 6. 



FIG. 5. Outline of posterior segments, from life, var. a, X 6. 



FIG. 6. Outline of section through head, X 38. 



FIG. 7. Section of mature segment, X about 8; a, a, ovaries; ft, b, uterine cavities with 

 clusters of ora ; b', !>', uterine cavities without ova; c, vagina; d, base 

 of iuvagiuated cirrus; c, e, convolutions of the vas dtfereus; /,/, testes. 



Rhynchobothrium lulllfer Lt. 



FIG. 8. Free proglottis, from life, X 15; a, bulb of cirrus partly protruding from 

 margin of segment ; I, vagina, near its exterior opening ; c, enlargement 

 of vagina into a receptaculum seminis ; d, d, vessels of the water- vascular 

 system ; e, e, spermatic capsules of testes ; /, cirrus bulb with vas deferens 

 entering the anterior part of the inner extremity; g, g, ova: /*, posterior 

 coils of vas defereus. 



FIG. 9. Cirrus of same everted with escaping spermatozoa, from life. 

 All figures made by Margaret B. Liuton. 





