894 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [176] 



PLATE XIV. 



Otobothrium crenacolle, gen. et sp. nov. 



Fig. 1. Outline of strobile, from life, X 8. 



Fig. 2. Outline of a more slender strobile, from life, X 10. 



Fig. 3. Proglottis, from alcoholic specimen, X 18 ; a, a, ovaries. 



Fig. 4. Proglottis, the central portion tumid on account of an aggregation of ova ; 



the size of the latter is somewhat exaggerated in the sketch; from an 



alcoholic specimen, X 12. 



Tetrarhynchus tenue, sp. nov. 



Fig. 5. Outline of strobile, from life, X 21. 

 Fig. 6. Proboscis, X about 400. 



Tetrarhynchus robustum, sp. nov. 



Fig. 7. Head and neck, from life, x 36. 



Fig. 8. Proboscis, X about 400. 



Fig. 9. Posterior segments with ova, from life, X 24. 



Tetrarhynchus bisulcatum Lt. 



Fig. 10. Outline of section through base of bothria, X 24; a, a, sulci separating the 

 bothria of the lateral pairs from each other; b, b, marginal spaces separ- 

 ating the pairs of bothria ; c, the four contractile bulbs of the probos- 

 cides ; for an enlarged sketch of one of these sections see Fig. 12. 



Fig. 11. Outline of section through the tubular neck and contractile bulbs, X 24. 



Fig. 12. Transverse section through a contractile bulb, X about 200: a, interior 

 cavity which in life is filled with a fluid containing a few refractile 

 granules, the function of the fluid, when compressed, being to evert the 

 proboscis ; b, section of retractor muscle ; c, section of muscular wall of 

 the bulb, showing the alternating layers of diagonal muscles. 

 All the figures made by Margaret B. Linton. 



