BY S. J. JOHNSTON. 359 



fibres— A ., Nervous system — CKs., (Esophagus— O.s., Oral sucker — 

 O., Ovary— O.d., Oviduct— Oo^., Ootype— /^., Penis— Fh., Pharynx 

 — F.ph., Praepharyux — Fr., Prostate — K.s., Receptaculum seminis 

 — R.S.U., Receptaculum seminis uterinum — S.g., "Shell-glands" — 

 T., Testis — h't., Uterus — 'Fag., Vagina or Metraterm — V .d., Vas 

 deferens — V.s., Vesicula seminalis — V .sh., Ventral sucker — Y.d., 

 Yolk-duct — Y.g., Yolk-glands — Y.r., Yolk-reservoir. 



Figures 1-17 are from drawings; 18-80 from microphotographs. 

 All the figures are from the ventral surface, except where stated 

 otherwise. 



Fig.l. — FoJystomum hulliense (x 40). G.i.c, genito-intestinal 

 canal — Kk., large hooks on disc — Vag.p., vaginal papillae — 

 Fig. la., one of the large hooks (x290) — Fig. lb., one of the 

 larval hooks (x290). 



Fig. 2. — Diagram of the genital organs of F. hulliense. G.i.c, 

 genito-intestinal canal — \ a<j.p., vaginal papillae — Vag.r., 

 sperm-reservoir at the beginning of the vaginal canal. 



Fig. 3. — Diplodiscus megalochrus (x37). B.d., buccal diverticu- 

 lum — c.d., central disc of F.sk., posterior sucker. 



Fig. 4. — Volichosaccus trypherus (x 33). 



Fig. 5. — Diagram of the female organs of D. trypherus. 



Fig. 6. — Excretory system of D. trypherus (x61). 



Fig. 7. — DoHchosaccus ischyrus (x43). 



Fig. 8. — Volichosaccus diamesus (x61). 



Fig. 9. — Brachysaccus anartius (x43). 



Fig. 10. — Brachysaccus symmetrus (x96). 



Fig. 11. — Fneumonoeces australis (x84). 



Fig.l2. — Gorgodera australiensis (x84). 



Fig. 13. — Mesocoelium mesembrinum (x33). 



Fig. 14. — Mesocculium oligoon (x60). 



Fig. 15. — Mesocoelium megalooii (x84). 



-big. 16. — Fleurogenes freycineti (x60). 



Fig. 17. — Fleurogenes solus (x60). 



Fig. 18. — L.S., Folystomum (xl30), passing through the middle of 

 a posterior sucker, showing the connective tissue plug, re- 

 tractor muscle, etc. 



Fig. 19. — L.S., FolystoinHm (x210), through the oral sucker. 



Fig. 20. — T.S., Folystomum (x255), through pharynx, buccal 

 pocket, and cerebral ganglia. 



Fig. 21. — T.S., Folystomum (xl60), through excretory vesicles. 



Fig. 22. — T.S., Folystomum. (xl30), through ovary, uterus, vas 

 deferens. 



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