A Contribution t<> Iho Aiialomy of Siren laccrtiiia. ß^O 



causiug 110 increase of the sensory surface. The large hitenil i»ar- 

 tition which separates the two cavities, bears no smell -buds, being 

 covered simply with columnar ciliated epithelium and olfactory cells. 

 In the region of this partition, the smell -buds are confined to 

 the roof of the cavity and are not well separated from each other. 

 Farther forward, in the main cavity as well as in the accessory 

 cavities, there are no well formed smell-buds, but the entire extent 

 of surface appears to be covered by olfactory cells, interrupted only 

 irregularly and occasionally by partitions of connective tissue, similar 

 to those in the posterior portion. 



F. Nerves of the nasal region. 



The nerves found in the nasal region are the following: 



1) Olfactorius I. 



2) Ramus ophthalmicus superficialis 



3) Ramus ophthalmicus profundus I ... V. 



4) Nervus nasalis externus 



5) Nervus nasalis internus 



6) Ramus palatinus anterior VIL 



Their general position is indicated by the section C, fig. 12, and 

 their distribution by the diagram of the nasal region, fig. 11. 

 A detailed description is as follows. 



1) Olfactorius. The olfactory nerve enters the capsule through 

 a large foramen in the ethmoid bone. Its fibres take a direction al- 

 most laterally outwards from the brain, thus lying nearly at light 

 angles with the other nerves which he near it. 



2) This nerve rests upon the roof of the nasal capsule without 

 entering it. It supplies the skin of this region by small branches, 

 the main stem continuing to the rostrum. 



3) The deep ophthalmic nerve enters the capsule at its posterior 

 border, and runs first underneath its roof, separated from the pre- 

 ceding only by the cartilage. Anteriorly it passes through the cartila- 

 ginous sheath above described, and appearing here as a brush of fine 

 fibres, becomes the principal nerve of sensation to the rostrum. In 

 the posterior third of its intracapsular course, it runs in intimate 

 relation to the olfactory from which it can generally be easily distin- 

 guished by the direction of its fibres. In the anterior two thirds it 

 is surrounded by the intermaxillary glands. 



4) This nerve, directly as it separates from the deep ophthalmic, 



