MORPHOLOGICAL STUDIES. 
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PLATE XVII. 
Fig. 21. — Section through facial ganglion Anlage, T. ocellata. Z. D, 
oc. 2. 
Fig. 22. — Section, trunk region, Mustelus 1 sc vis. Z. D, oc. 2. 
Fig. 23. — Section, trunk region, M. laevis. Z. F, oc. 2. 
Fig. 24. — Section, vagus ganglion, T. ocellata. Z. D, oc. 2. 
Fig. 25. — Section, auditory organ and ganglion, T. ocellata. Z. D, oc. 2. 
Fig. 26. — Section, spinal cord region, Pristiurus. Z. F, oc. 2. 
Fig. 27. — Section, auditory region, T. ocellata. Z. F, oc. 2. 
Fig. 28. — Section, trunk region, Pristiurus. Z. D, oc. 2. 
Fig. 29.— Section, vagus region of head, T. ocellata. Z. D, oc. 2. 
Fig. 30. — Section, trunk region, T. ocellata. Z. D, oc. 2. 
Fig. 31. — Section, trunk region, T. ocellata. Z. D, oc. 2. 
Figs. 32 — 36. — Sections, trunk region, Pristiurus. Z. D, oc. 2. 
The order from before backwards is 33, 34, 35, 36, 32. 
PLATE XVIII. 
Fig. 37. — Section, anterior head region, T. ocellata. Z. C, oc. 2. 
Fig. 37 — The small figure marked out in preceding section under high 
power, to show Anlage of a cranial ganglion. Z. F, oc. 2. 
Fig. 38. — Part of a section of head region, T. ocellata. Z. F, oc. 2. 
Fig. 39. — Section, head region, T. ocellata. Z. F, oc. 2. 
Figs. 40 — 42. — Portions of sections through head region of three Torpedo 
embryos. Z. F, oc. 2. 
Fig. 43. — Section, trunk region, Mustelus. Z. D, oc. 2. 
Fig. 44. — Portion of a section, trunk, T. ocellata. Z. F, oc. 2. 
Fig. 45. — Portion of a section of Mustelus through vagus region. Z. F, 
oc. 2. 
Fig. 46.— Section through auditory region of a Chick embryo. H. 9, oc. 2. 
Fig. 47. — Section, head region, T. ocellata. Z. F, oc. 2. 
Fig. 48. — Section, mid-brain region, Mustelus. Z. F, oc. 2. 
Fig. 49. — Section, region of anus, Mustelus. Z. D, oc. 2. 
Fig. 50. — Section, region of head, Mustelus. Z. C, oc. 2. 
Fig. 51. — Section, trunk region. Chick, eight somites. Z. F, oc. 2. 
PLATE XIX. 
Fig. 52. — Section, anus region, T. ocellata. Z. D, oc. 2. 
Fig. 53. — Section, trunk region, T. ocellata. Z. D, oc. 2. 
Fig. 54.— Section, trunk region, T. ocellata. Z. D, oc. 2. 
Fig. 55. — Section, trunk region, Chick, eight somites. Z. F, oc. 2. 
