RICH PLEXUSES AND LOOPED FILAMENTS. 225 



the surface of the tongue, and terminating in the pa- 

 pillae. The papillae, thus endowed with nervous influ- 

 ence, are the seat of the sense of taste." 



Of the fifth nerve (in man and in the horse) Prof. 

 Owen (quoting partly from Dr. Swan), says ("Odon- 

 tography," vol. i, pp. Ixv-vi) : 



" The nerves of the teeth are derived from the tri- 

 geminal, or fifth pair, of which the second division sup- 

 plies those of the upper jaw, the third division those 

 of the lower. In the human subject, the three dental 

 branches of the infra-orbital nerve intercommunicate 

 by their primary branches, from which, and from a 

 rich plexus formed by secondary branches upon the 

 membrane lining the antrnm, two sets of nerves are 

 sent off to the alveolar processes of the upper jaw; one 

 set (rami dentales) supplies the teeth, the other (rami 

 gingivales) the osseous tissue of the gums. The latter 

 agree in number with the intervals of the teeth, as the 

 proper dental nerves do with the teeth themselves. 

 These two sets are not, however, so distinct but that 

 some intercommunications are established between the 

 fine branches sent off in their progress to the parts 

 they are specially destined to supply. The rami den- 

 tales take the more direct course (through the middle 

 part of the osseous tissue to the teeth) penetrate the 

 orifices of the fangs, and form a rich plexus with 

 rhomboidal meshes upon the coronal surface of the 

 pulp, the peripheral elementary filaments returning 

 into the plexus by loops. In the lower jaw the dental 

 nerve, besides supplying the proper nerves to the teeth, 

 also forms a rich plexus, in which it is joined by some 

 branches from the division of the nerve that afterward 

 escapes by the foramen mentale, and from this plexus 



