112 J. B. JOHNSTON 



McKiBBEN, Paul S. 1911 The nervus terminalis in urodele Amphibia. Jour. 



Comp. Neiu'., vol. 21, no. 3. 

 Peter, Karl, 1902 Die Entwickelung des Geruchsorgans und Jakobson'schcn 



Organs in der Reihe der Wirbelthiere, O. Hertwig's Handbueh der 



Entwickelungslehre. 

 PiNKrs, Felix 1894 tJber einen noch nicht beschriebenen Hirnnerven des 



Protopterus annectens. Anat. Anz., Bd. 9. 



1895 Die Hirnnerven des Protopterus annectens. Morph. Arb., Bd. 



4, p. 275. 

 Read, E. A. 1908 A contribution to the knowledge of the olfactory apparatus 



in dog, cat and man. Amer. Jour. Anat., vol. 8. p. 40. 

 Sewertzoff, a. N. 1902 Zur Entwickelungsgeschichte des Ceratodus forsteri. 



Anat. Anz. Bd. 21. 

 Sheldon, R. E. 1909 The nervus terminalis in the carp. Jour. Comp. Xeur., 



vol. 19, no. 2. 



ABBREVIATIONS 



b.c, bulbus olfactorius n.olf.v., nervus olfactorius, ventral root 



c, choana n., narial opening 



c.d., commissura anterior H..5ac, nasal sac 



f.i., foramen interventriculare n.i., nervus terminalis 



f.o.d., formatio olfactoria, dorsal por- olf.ep., olfactory epithelium 



tion P'lt-, palate 



f.o.v., formatio olfactoria, ventral por P-h-, primordium hippocampi 



tion r.n., recessus neuroporicus 



g.i., ganglion terminale r.p., recessus praeopticus 



hem., hemisphere s., corpus striatum 



m., margin of lamina supraneuroporica /., tectum mesencephali 



med.div., medial diverticulum of nasal t.c, tela chorioidea 



sac t.o., tuberculum olfactoriuni 



n.o.a., nucleus olfactorius anterior v.l., lateral ventricle 



v.olf., nervus olfactorius r-//.o., vomero-nasal organ 



n.nlj.d., nervus olfactorius, dorsal root v.tr., velum transversum 



Fig. 1 Pig, 22 mm. Model of rostral part of right hemisphere, seen from 

 the medial surface. The bulbus olfactorius is not clearly delimited by grooves 

 but the root of the olfactory nerve shows its position. The ganglion terminale 

 accompanies the root and four branches of the nervus terminalis which runs 

 obliquely across the roots of the olfactory nerve. The point r.p. in the model is 

 just above and rostral to the preoptic recess. 



Fig. 2 Pig, 19 mm. Sagittal section through the rostral part of the left 

 hemisphere. The spindle-shaped ganglion terminale is closely related to a broad 

 collection of lightly staining cells which follows the contour of the bulbus olfac- 

 torius. These latter cells belong to the neurilemma cells of the olfactory nerve. 

 Note that the root accompanied by flattened cells is directed toward the neuro- 

 poric recess. 



