Wakd. — Nectonema. 



PLATE IV. 



Fig. 53. Posterior end of male viewed as a transparent object in clove oil. 2. C 

 X 165. 



Pig. 54. Wall of dorsal sac showing nuclei. Ehrlich's haematoxylin. Apoclir. 

 4 mm. Compens. Oc. 8. X 725. 



Fig. 55. Spermatozoa (unripe ?). Biilimer's hematoxylin. Apochr. 4 mm. Com- 

 pens. Oc. 12. X 1,000. 



Fig. 56. Posterior end of female viewed as a transparent object in clove oil. 2. A. 

 X95. 



Fig. 57. Sagittal section through posterior end of female, showing slight develop- 

 ment of anal ganglion. Ehrlich's haematoxylin. 2. A. X 95. 



Fig. 58. Transverse section through middle of body of female filled with eggs. 

 Bohmer's haematoxylin. 3. A. X 130. 



Fig. 59. Transverse section through body wall of nearly mature female to show 

 remains of cell layer (*) within the muscular layer. Bohmer's haema- 

 toxylin. 3. C. X 330. 



Fig. 60. Section of immature egg. Ehrlich's haematoxylin. 3. D. X 540. 



Fig. 61. Section through nearly ripe egg. Bohmer's haematoxylin. 3. D. X 540. 



Fig. 62. Egg after contact with sea-water. Glycerine preparation. 3. D. X 560. 



