34.8 
Part III. — Ninth Annual Report 
4. Holt, E. W. L., "Eggs and Larvae of Teleosteans, West Coast of Ireland," 
Sci. Trans. Roy. Diiblin Soc, vol. iv. , 1891. 
5. Prince, E. E., "Dev. of Pectoral Fin in Oss. Fishes," Inaugural Dissertation, 
Glasgow, 1890. 
6. RafFaele, F., " Le uova galleggianti e le larve de Teleostei nel Golfo di Napoli," 
Mitth. Zool. Stat. Nap., 1888. 
7. Ryder, John A., "On the Origin of Heterocercy," Rep. U.S Fish Comm., 1884. 
DESCRIPTION OF PLATES. 
Lettering adopted in the figures. 
a, anus. 
aiL, otocyst. 
caps, capsule of egg. 
cp, cortical protoplasm. 
c, eye. 
era, unpaired embryonic fin. 
ec, ectoderm, corneous. 
ecn, ectoderm, neurodermal. 
fh, forebrain. 
Ir, liver. 
mo, medulla oblongata. 
msn, mesentery. 
7ny, myotomes. 
ne, nerve (?). 
nc, notocliord. 
ov, ovary. 
og, oil-giobule. 
pf, pectoral fin. 
pt, pigment. 
pn, pineal gland. 
sg, archiiiephric duct. 
so, somatopleure. 
sp, median dorsal spines. 
ss, serous spaces in and around 
trunk, &c. 
vf, ventral fin. 
X, dorsal aggregation of mesoderm. 
y, -loose cells of mesoderm. 
yk, yolk. 
z, osteoid matter (like chitin). 
Plate XIV. 
Fig. 1. Ovum of LopMus piscatorius — magnified. 
Fig. 2. Embryo just hatched, showing chambers around the yolk, x 12. 
Fig. 3. ,, fifth day, with dorsal process and paired fins, x 12. 
Fig. 4. ,, ninth day, ventral aspect, x 12. 
Fig. 5. ,, just before hatching, x 35. 
Fig. 6. ,, fifteenth day, dorsal aspect. 
Fig. 7. fifteenth day, ventral aspect. 
Fig. 8. fifteenth day, with three dorsal spines and long ventral fins, x 18. 
Plate XV. 
Fig. 9. Embryo nearly ready to hatch. Trans, section through pectoral region, x 45. 
Fig. 10. ,, more advanced than fig. 9. ,, ,, ,, x 45. 
Fig. 11. ,, nine days old. ,, ,, ,, x 45. 
Fig. 12. fifteen days old. ,, ,, ,, x 45. 
Fig. 13. ,, ninth day. Transverse section through yolk and pelvic fin, x 75. 
Fig. 14. ,, first day. ,, ,, ,, tail posterior to anus, x 70. 
Fig. 15. ,, fifteenth day. ,, ,, rectum (showing ovary), x 70. 
Fig. 16. ,, ninth day. ,, ,, ,, first dorsal spine, x.l50 
Fig. 17. ,, ninth day. ,, ,, ,, fore-brain, x 45. 
Fig. 18. ,, fifteenth day. ,, ,, ,, pineal gland, &c., x 45. 
Fig. 19. ,, fifth day. ,, ,, ,, medulla oblongata, x 45^ 
