37G EDWIN S. GOODRICH. 



PLATE 12. 



Fig. 13. — The skeleton and muscles of the first dorsal fiu of an adult. 



Fig. 14. — Oblique longitudinal section of the pelvic fin reconstructed in 

 fig. 9. Traces of segmentation extend into the basipterygial region. 



Fig. 15. — Reconstructed skeleton of the first dorsal fin of an embrjo 

 55 mm. long. Precartilage extends along the dorsal edge. 



Fig. 16. — Portion of the vertebral column, skeleton of the first dorsal Gn 

 (without the precartilage), and radial muscles of the embryo 55 mm. long 

 represented in fig. 15. 



Fig. 17a. — Reconstructed muscle-buds of the first dorsal fin of an embryo 

 30 mm. long. 



Fig. 17b. — Longitudinal vertical section of the first dorsal fin, drawn to the 

 same scale as fig. 17a and taken from the same series, showing the first indi- 

 cation of the skeleton. 



Fig. is. — Longitudinal section of the pelvic fin of an embryo, 33 mm. long. 



Fig. 19. — The base of three radial muscles, showing connecting strands of 

 tissue {an.). Embryo 28 mm. long. ' Cam. Ob. Z. D.,' oc 2. 



Fig. 20. — Longitudinal vertical section of the first dorsal of an embryo 

 33 mm. long, reconstructed in fig. 7. 



PLATE 13. 



Fig. 21. — Dorsal branches of the spinal nerves 2'l-57 of an adult, showing 

 the longitudinal collectors near the dorsal fins. 



Fig. 22. — Similar figure of an individual about 25 cm. long. The skeleton 

 of the fins is indicated. 



Fig. 23. — First dorsal fin of the same individual showing the radial 

 muscles. 



Fig. 24. — Nerve-supply of the anterior region of the ventral lobe of the 

 caudal fin of an adult. The muscles are shown only in one part. The motor- 

 nerves are in black and the sensory are drawn in blue. * indicates twigs 

 which appear to mix with neighbouring nerves. 



PLATE 14. 



Fig. 25. — Embryo, 19 mm. long, mounted in Canada balsam. Cam. 



Fig. 2C. — Skeleton (indicated by a dotted line), and muscles of the first 

 dorsal fin of an adult. The nerve-plexus at tiie base of the fin is shown and 

 the beginning of the collector of the second dorsal fin. 



Fig. 27.— Diagram to illustrate the transposition of limbs. 



