JOURNAL OF MICROSCOPICAL SCIENCE. 
EXPLANATION OF PLATES XXXIV & XXXV, 
Illustrating Mr. Sydney J. Hickson’s Memoir on the 
Eye of Pecten.^^ 
Fig. 1. — A diagrammatic sketch of an eye of Picien maximus. a. The 
cornea, b. The transparent basement membrane supporting the epithelial 
cells of the cornea, c. The pigmented epithelium, d. The lining epi- 
thelium of the mantle, e. The lens. f. The ligament supporting the lens. 
g. The retina, h. The tapetum. Jc . The pigment. /. The optic nerve. 
m. The retinal nerve, n. Complementary nerve, p. The circumpaleal 
nerve (Duvernoy). q. A supplemental nerve from pedal ganglion. 
Fig. 2. — Epithelial cells of cornea. 
Fig. 3. — Section through the junction of the pigmented epithelium with 
corneal epithelium. 
Fig. 4. — Vertical section through eye of Pecteti maximus. a, b. Cornea. 
c. Pigmented epithelium, d. Mantle epithelium, e. Lens. g. Retina. 
h. Tapetum. k. Pigment. 1. Section of optic nerve. 
Figs. 5, 6. — Isolated rods. Q > a . — Diagrammatic sketch of a- central 
rod. /?./. Posterior limb. Membrane pierced by rods. a. /.Anterior 
limb. s.r. Spindle-shaped portion of rod. n. Nerves. 
Figs. 7. — Transverse sections through eye of P. maximus. a. Rods in 
section, b. Tapetum. c. Pigment, d. Retinal nerve. 
Fig. 8. — Vertical section of the eye of Pecten maximus, showing the 
nerve dividing into retinal and complementary branches. 
Fig. 9. — Vertical section of the eye of Pecten maximus, showing the 
termination of the retinal nerve. The retina has dropped out, and the * 
frayed-out end of the nerve remains. 
Fig. 10. — Section of eye of Pecten opercularis. 
Fig. 11. Retina («) of P. opercularis, {b) of P. jacoberus, (e) P. maximus. 
Note. — A horizontal section means a section made in the same plane as 
the mantle. A transverse section, in a plane at right angles to I lie eye 
stalk. A vertical section, in a plane at right angles, both to the plane of the 
mantle and the last-named plane. 
