51 



Fio-. 4. rjepcoplitlicirK.s perfm-alis, " chalimus " stage. 



X 26. 

 Fig. 5. Caligus rapax. early "chaliinuK" stage attached 



to tin ray of young cod, the Hue d' c' represents 



the surface of the skin, x 54"4. 

 Fig. 6. CaUijus rapax, "chaHmus" stage, previous to 



throwing off the tilament attachment. On tail 



of young lunipsucker. X 15*24. 

 Fig. 7. Caligus rapax, mature, part of the frontal plate 



showing a lateral sucker, x 2-2. 



Plate II. 



Lt'jit'ojjJitlwirHs pectoral is. 



Fig. 1. Female, ventral view, showing tlie various 

 appendages and their muscles. x IT. 



Fig. 2. Female, dorsal view, showing the chief muscles 

 and hlood currents. The arrows indicate the 

 course of the blood. x 17. 



Fig. -i. Female, ventral view, showing the digestive 

 gland, its duct and alimentary canal. x 17. 



Fig. 4. Female, ventral view, showing the reproduc- 

 tive organs. x 17. 



Fig. 5. Male, ventral view, showing the reproductive 

 organs. x 26. 



Fig. G. Grenital segment and abdomen of an immature 

 female, ventral view, showing vulva (vu.). x 40. 



Fig. 7. Spermatophores detached from genital openings 

 of a female. x 25. 



Fig. 8. Mouth from the anterior base, with the 

 mandibles inside, showing the muscles and 

 ducts of digestive gland. x 25. 



Fig. 9. Digestive gland. x 77. 



Fig. 10. Longitudinal section of the ovary. x 50. 



