224 
J. BEARD. 
DESCRIPTION OF PLATES XVI— XXI, 
Illustrating the Memoir by Dr. Beard on “The Development 
of the Peripheral Nervous System of Vertebrates. Part I.” 
List of References. 
1. Hi, v, vii, &c. Olfactory, motoroculi, trigeminal, facial, &c., nerves. 
a. Anterior root. al. c. Alimentary canal, au. o. Auditory organ. Or. Brain. 
Or. gl. Branchial or lateral ganglion, cl. Cleft, e. Epiblast. f. Or. fore-brain. 
f. gl. Facial ganglion, gl. Ganglion, gl. gl. Glossopharyngeal, g. A. Gan- 
glionic Anlage. h. Or. Hind-brain. h. c. Head-cavity, or head-somite. 
i. e. Indifferent epiblast. m. Mesocephalic ganglion, m. Or. Mid-brain, me. 
Mesoblast. n. Notochord, n. s. Nervous system, olf Olfactory, p. g. 
Parapodial ganglion, s. e. Neuroepithelium, sp. Spinal, sp. c. Spinal cord. 
All figures, except Fig. 64, are drawn under Zeiss’s camera lucida. The 
magnification is indicated by such letters as Z. D, oc. 2, which signifies Zeiss’s 
objective D, ocular No. 2. The objectives used were those of Zeiss and Hart- 
nack, and are distinguished as Z. and H. respectively. Except Figs. 90 — 93, 
96, 100, 101, which are from longitudinal frontal sections, the figures represent 
transverse sections. 
All figures are reduced in the plates to two-thirds of their original size. 
PLATE XVI. 
Figs. 1 — 3. — Sections through the trunk of a Torpedo embryo. Z. D, oc. 2. 
Fig. 4. — Section through the head region of Torpedo ocellata. Z. D, 
oc. 2. 
Fig. 5. — Section, trunk region, T. ocellata. Z. D, oc. 2. 
Figs. 6 and 7. — Sections, head region, T. ocellata. Z. D, oc. 2. 
Figs. 8 and 9. — Sections, trunk region, T. ocellata. Z. D, oc. 2. 
Fig. 10. — Section, mid-brain region, T. ocellata. Z. D, oc. 2. 
Fig. 11. — Section, head region, T. ocellata. Z. D, oc. 2. 
Fig. 12. — Section, head region, T. ocellata. Z. D, oc. 2. 
Fig. 13. — Section, trunk region, T. ocellata. H. 8, oc. 2. 
Fig. 14. — Section, trunk region, T. ocellata. Z. D, oc. 2. 
Fig. 15. — Section, trunk region, T. ocellata. Z. D, oc. 2. 
Fig. 16. — Section, trunk region, T. ocellata. Z. D, oc. 2. 
Fig. 17. — Section, trunk region, T. ocellata. H. 8, oc. 2. 
Fig. 18. — Section, head region, T. ocellata. Z. D, oc. 2. 
Figs. 19 and 20. — Sections, brain region, of two Torpedo embryos. 
Origin of olfactory neural ganglion. Z. D, oc. 2. 
