68 H. W. MARETT TIMS. 
19. Tuomson, J. Sruart.—‘ The Periodic Growth of Scales in Gadide and 
Pleuronectide as an Index of Age.” ‘Journ. Marine Biolog. Assoc.,’ 
vol. vi, No. 3, 1902, pp. 373-375. 
20. Witt1amson, W. C.—“ On the Microscopic Structure of the Scales and 
Dermal Teeth in some Ganoid and Placoid Fish.” ‘ Phil. Trans. Lond.,’ 
1849, pt. 2, pp. 435-476. 
21. WituiaMson, W. C.—“ Investigations into the Structure and Development 
of the Scales and Bones of Fishes.” ‘ Phil. Trans. Lond., 1851 
pp. 643-702. 
EXPLANATION OF PLATE 6, 
Illustrating Mr. H. W. Marett Tims’s paper on ‘The 
Development, Structure, and Morphology of the Scales 
in some 'l'eleostean Fish.” 
Fig. 1.—Surface view of epidermis of G. virens, showing the chromato- 
phores and the openings of the glands. 
Fic. 2.—Section through the same. 
Fig. 3.—Section through the dermis of G. virens (4°6 em.) after treat- 
ment with acid alcohol. 
Fig. 4.—Section througha scale of G. virens (56 cm.). From a specimen 
to which no acid had been applied. 
Fic. 5.— View of the external surface of a scale of G. virens (9 em.). 
Fig. 6.—Ditto, G. callarias (24 feet). 
Fic. 7.—Section through scale of G. callarias. 
