PLATE 3. 



Fig. 14. Left vestibular ridge of Sagitta enfiata. X 240. 

 Fig. 15. Left vestibular ridge of Sagitta liexaptera. X 80. 

 Fig. 16. Left vestibular ridge of Sagitta lyra. X 80. 



Fig. 17. Left vestibular ridge of Sagitta gigantea Broch. Specimen 

 from Norwegian North Atlantic. X 80. 



Fig. 18. Left vestibular ridge of Sagitta bipimctata. X 240. 



Fig. 19. Double vestibular ridge of Sagitta bi punctata. X 240. 



Fig. 20. Left vestibular ridge of Sagitta serratodentata. X 240. 



Fig. 21. Left vestibular ridge of Sagitta planltonis. X 80. 



Fig. 22. Left vestibular ridge of Sagitta neglecta. X 240. 



Fig. 23. Left vestibular ridge of Spadella draco. X 240. 



Fig. 24. Left vestibular ridge of Sagitta elegans. X 240. 



Fig. 25. Teeth of EukroJinia subtilis. X 240. 



ABBREVIATIONS. 



b. — barbs. n. — notch. 



ext. proc. — external process. pap. — papillae. 



ext. t. — external tooth. w. — wing of ridge. 

 int. t. — internal tooth. 



176] 



