Fig. 65. Transverse section through the same embryo as fig. 64 further back, shewing the posterior part of the air-bladder (ab).
Fig. 66. Viscera of an adult female, 100 centims. in length, shewing the alimentary canal with its appended glands in natural position, and the air-bladder with its aperture into the throat (ab´). The proximal part of the duodenum and the terminal part of the intestine are represented as cut open, the former to shew the pyloric valve and the apertures of the pyloric cæca and bile duct, and the latter to shew the spiral valve.
This figure was drawn for us by Professor A. C. Haddon.
Fig. 67. Transverse section through the tail of an advanced larva, shewing the neural and hæmal processes, the independently developed interneural and interhæmal elements (is), and the commencing dermal fin-rays (df).
Fig. 68. Side view of the tail of a larva, 21 minims. in length, dissected so as to shew the structure of the skeleton.
Fig. 69. Longitudinal horizontal section through the vertebral column of a larva, 5.5 centims. in length, on the level of the hæmal arches, shewing the intervertebral rings of cartilage continuous with the arches, the vertebral constriction of the notochord, &c.
Figs. 70 and 71. Transverse sections through the vertebral column of a larva of 5.5 centims. The red represents bone, and the blue cartilage.
Fig. 70. Through the vertebral region, shewing the neural and hæmal arches, the notochordal sheath, &c.
Fig. 71. Through the intervertebral region, shewing the intervertebral cartilage.