CRANIAL NERVES OF CHIMiERA MONSTROSA. 



679 



I.C. 



In. 

 in.r. 



i.o. 



i.r. 



L. 

 L.C. 



M. 

 Md. 

 N.S. 



0. 

 O.L. 



Op. 

 PC. 



pt. 



r.b. 



r.l. 

 S.C. 

 Sch. 



s.o. 

 S.O. 



S.O\ 



S.O 2 . 



s.r. 



Th. 



V.C. 



Infra-orbital canal (red). 



Intestinal (vagus). 



Inferior rectus. 



Inferior oblique. 



Internal rectus. 



Lateralis (lateral line system). 



Lateral canal (brown). 



Mouth. 



Medulla. 



Nasal sack. 



Branchial aperture formed by opercular fold. 



Olfactory lobes. 



Optic lobes. 



Profundus canal (green). 



Pituitary body. 



Radix brevis. 



Radix longa. 



Supra-orbital canal (blue). 



Sclrwalbe's ciliary ganglion and nerve. 



Superior oblique. 



Superficial ophthalmic (lateral line system). 

 For roots, see fig. 3. 



Partial separation of above into two band- 

 like nerves. The dorsal one is thinner and 

 not so broad as the ventral. 



Superficial ophthalmic group of ampullse (com- 

 posed on each side of a large and a small 

 group). Note distribution of superficial 

 ophthalmic nerve to this group. * Supply 

 small isolated groups of ampullae. 



Superior rectus. 



Thalamencephalon. 



Position of visceral clefts. 



//. 



///. 

 III 1 . 

 III 2 . 

 IIP. 

 III*. 



IV. 



IV\ 



V. 



VK 



v\ 



V 3 . 



v\ 



VK 

 V 6 . 



v\ 



V s . 



V s . 



F 10 . 



v n . 



VI. 



vn. 



VIII. 



IX. 

 X. 



Olfactory nerves. 



Optic nerve. 



Roots of oculo-motor. 



Branch of above to superior rectus. 



Dorsal ramus of oculo-motor to internal rectus. 



Ventral ramus to inferior oblique. 



Branch of above to inferior rectus. 



Trochlearis emerging from furrow separating 



optic lobe and medulla. 

 Distribution of above to superior oblique. 

 Position of roots of trigeminus (see fig. 3). 

 Gasserian ganglion. 

 Profundus and its ganglion. 

 Branch from profundus supplying two sense 



organs of supra-orbital canal ( = profundus 



canal) and also sending twigs to skin. 

 Trunk of trigeminus. 

 Maxillary or superior maxillary. 

 Mandibular or inferior maxillary. 

 Branch really from mandibular to masseter 



muscle of jaw. 

 Anastomoses between buccal and maxillary 



nerves. 

 Superficial ophthalmic of Vth. 

 Motor (?) branch of profundus. 

 Visceral branch of Vth. 

 Abducens. 



Distribution of above to external rectus. 

 Auditory. a, to anterior ampulla ; b, to 



external ampulla; c, to sacculus; d, to 



posterior ampulla. 



Glossopharyngeal ) ,. ,. 



r J ° > diagrammatic. 

 Vagi 1, 2, and 3 J ° 



Fig. 2. Semi-diagrammatic figure of glossopharyngeal, vagus, and cranial spinal nerves of CJiimcera monstrosa, 

 seen from left side. The visceral skeleton was drawn from a preparation in Prof. Howes' 

 Laboratory, Royal College of Science, South Kensington. 



B.B. Basi-branchial. 



B.B 1 . Basi-branchial of last or fifth visceral arch. 

 B.H. Basi-hyal. 

 C.B. Cerato-branchial. 

 C.H. Cerato-hyal. 

 Cp. Median ventral copula. 

 Cp 1 . Lateral ventral copulae. 

 Cp n . Copula between fused fourth and fifth opi- 



branchials and pectoral girdle. 

 E.B. Epi-branchial. 

 E.B 1 . Epi-branchial of fused fourth and fifth 



visceral arches. 

 H.B. Hypo-branchial. 

 H.B 1 . Hypo-branchial of fourth and fifth visceral 



arches. 



VOL. XXXVIII. PART III. (NO. 19). 



H.M. Hyomandibular. 

 I. Intestinal (vagus). 



L. Root lateralis (lateral line system). Roots 

 of branchial divisions of vagus lie under 

 cover of this root. Note position of vagus 

 foramen. 

 Md. Medulla. 

 Mn. Lower jaw. 

 0. Opercular cartilages supporting opercular 

 fold and hyoidean demibranch. 

 P.B. Pharyngo-branchial. 

 P.B\ Pharyngo-branchial of third and fourth and 



fifth branchial arches. 

 P.F. Skeleton of pectoral fin. 

 P.G. Pectoral girdle. 



5 B 



