36 NERVE COMPONENTS OF BONY FISHES. 



From the innervation of these organs I incline to regard 

 them, like the buds on the top of the head, as belonging 

 to the communis system. Of course it does not necessarily 

 follow that the accessory lateral lines of Fierasfer, Amia, 

 etc. , which are innervated by branches of the r. lateralis 

 vagi, are of the same nature. See the further discussion 

 of the r. lateralis accessorius in Section 12. 



Upon the head there are several series of naked cutane- 

 ous organs which are clearly innervated by the lateral line 

 nerves and which I homologize with the pit-lines of Amia. 

 See fig. 5. 



One row of four large organs {o.i to 0.4) follows the 

 ventral edge of the operculum behind the fourth pore of 

 the opercular canal. One organ (and I think usually two) 

 lies on the dorsal surface of the operculum behind the 

 sixth pore of the opercular canal {o.j). These five organs 

 are innervated from the r. opercularis superficialis VII 

 and obviously from the coarse-fibred lateralis component. 

 Another similar organ {0.6) lies in front of the opercular 

 canal at the level of the fifth pore and is supplied by the 

 first branch of the r. mandibularis VII. 



Along the course of the horizontal limb of the opercular 

 canal and just external to the canal are three groups of 

 similar, but smaller, organs innervated respectively by 

 the first, fourth and sixth branches of the r. mandibularis 

 VII. A group of three similar organs lies along the 

 course of the mandibular canal and is supplied by the 

 eighth branch of the r. mandibularis VII. A single organ 

 on each side [man. c.) lies mesally of the cephalic end 

 of the mandibular canal, the two forming a mandibular 

 commissural line. 



There are four organs in the nasal region which are 

 supplied by the r. buccalis {a. d. e. f.) which appear also 

 to form a similar pit-line, making, together with a line 

 from the opposite side, a maxillary commissure. About 

 the anterior nasal aperture there are five organs, two of 

 which {b. c.) are supplied by the r. buccalis, and three 

 {g. h. i.) are supplied by the r. ophthalmicus superficialis. 

 They are of uncertain nature. I have provisionally 



