BRANCHIAL SENSE ORGANS OF ICHTHYOPSIDA. 219 



DESCRIPTION OE PLATES VII, VIII, AND IX. 



In most cases the objective and ocular used for each drawing are 

 denoted by letters, such as Z. d, oc. 2, which signify Zeiss's objective 

 d, ocular No. 2. The figures are mostly camera drawings, and are all 

 reduced to one third of their apparent enlargement. 



ALPHABETICAL LIST OP REFERENCES. 



I, in, v, vii, <fec, Olfactory, motor oculi, trigeminal, facial, &c, nerves. 

 al.c. Alimentary canal. aucl. and au.o. Auditory organ. au.gl. 

 Auditory ganglion. au.n. Auditory nerve. br. Brain. br.gl. 

 Branchial ganglion, br.o. Branchial sense organ, c.b. Nerve con- 

 necting ciliary and Gasserian ganglia, c.gl. and cil.gl. Ciliary gan- 

 glion, cil. Ciliary, cl. Cleft, cl. vi Sixth cleft, ep. Epiblast. f.br. 

 Fore-brain, f.gl. Facial ganglion, fac. Facial. Gass. Gasserian. 

 G.gl. Gasserian ganglion, gl.gl. Glossopharyngeal ganglion, gloss. 

 Glossopharyngeal, h.br. Hind-brain, h.c. Head-cavity. k.c 2 Second 

 head-cavity. hy.cl. Hyoid cleft. i.e. Indifferent epiblast. l.l. 

 Lateral line. l.n. Lateral nerve, l.m. Lateral muscle plates, m. 

 Mouth, m.br. Mid-brain, me. Mesoblast. ms. Inter-muscular septa. 

 n. Notochord. n.c.gl. Nerve of ciliary ganglion. n.s. Nervous 

 system, olf.gl. Olfactory ganglion, olf.n. Olfactory nerve, olf.o. 

 Olfactory organ, opfcpro. Ophthalmicus profundus. op>.s. Ophthal- 

 micus superficialis of fifth nerve, p. br.o. Primitive branchial sense 

 organ, p.b.n. Pree-branchial nerve, p.f. Portio facialis of ophthal- 

 micus superficialis — one supra-branchial nerve of facial, p.n. Post- 

 branchial nerve, p.r. Posterior root. r.b. Ramus buccalis, the second 

 supra-branchial nerve of the facial, sb.n. Supra-branchial nerve, sp.c. 

 Spinal cord, sp.gl. Spinal ganglion, sm.b. Smell-buds, s.t.v. Supra- 

 temporal branch of vagus 1. s.t.g. Supra-temporal branch of glosso- 

 pharyngeal, vg.gl. Vagus ganglion, vg. 1. Vagus ganglion 1. 



Plate VII. 

 Fig. 1. Olfactory nerve just fusing with olfactory thickening. Torpedo 



ocellata. Z. d, oc. 2, camera, olf.n. Olfactory nerve, olf.o. 



Olfactory thickening. 

 Fig. 2. Olfactory ganglion {olf.gl.) and olfactory thickening (olf.o.) 



fused together. Torpedo ocellata. Z. d, oc. 2, cam. luc. 



