PARASITIC COPEPODA. 209 



EXPLANATION OF THE PLATES. 



PLATE I. Lepeophtheirus brachyurus, HELLER, and Lepeophtheirus cesopus, n. sp. 



Fig. 1. Lepeophtheirus brachyurus, dorsal view of female. 



2. First and second antenna and first maxilla. 



,, 3. Mouth-tube and second maxillae. 



4. Second maxilliped. 



5. Furca. 



Figs. 6 to 9. First, second, third, and fourth swimming legs. 



Fig. 10. Genital segment, ventral surface, showing cement glands and sperm receptacle. 



,, 11. Lepeophtheirus cesopus, dorsal view of female. 



12. Second antenna and first maxilla. 



1 3. Mouth-tube and second maxillae. * 



14. Second maxilliped. 



Figs. 15 to 18. First, second, third, and fourth swimming legs. 



Fig. 19. Ventral surface of genital segment, showing cement glands and spermatophores. 



PLATE II. Trebius exilis, n. sp. 



Fig. 20. Dorsal view of adult female. 



21. male. 



22. Second antenna of male. 



23. Mouth-tube and second maxilla. 



24. First maxilliped. 



25. Second maxilliped. 



26. Furca. 



Figs 27 to 30. First, second, third, and fourth swimming legs. 



Fig. 31. Ventral surface of genital segment, showing the cement glands and spermatophores. 

 Figs. 32 and 33. Dorsal views of young females in different stages of development. 



PLATE III. Dissonus spinifer, n. gen. et n. sp. 



Fig. 34. Dorsal view of female. 



35. male. 



,, 36. Second antenna of male. 



37. Ventral view of anterior part of carapace, showing relative size and position of antennae and 

 mouth-parts. 



38. Bony frame work of mouth-tube, and the second maxillae. 



39. Second maxilla of male. 



40. Mandible. 

 Figs. 41 and 42. First and second maxillipeds. 



43 to 46. First, second, third, and fourth swimming legs. 

 Fig. 47. Ventral surface of genital segment of male. 



2 E 



