2 34 CLAPP. [Vol. XV. 



main portion of the buccalis passes directly downward to the 

 floor of the orbit (Fig. 13, biic.f}) enclosed for some distance 

 in the same sheath with the rnaxillaris of the fifth. It then 

 again divides, one branch being directed toward the median 

 line supplying the six antorbital organs, while the other sends 

 branches to the seven organs which constitute the maxillary 

 portion of the infraorbital line (Fig. 23). The two organs 

 (9, 10) of the infraorbital line, corresponding to those inner- 

 vated by the otic branch in Amia (Fig. 21), are in Batrachus 

 supplied by a branch from the R. buccalis facialis (Figs. 

 22 and 23). 



Opercnlo-mandibitlar Ihic. — The organs of this line are 

 innervated by the R. mandibularis externus facialis. Organ 12, 

 — a free organ, — together with the most dorsal of the two 

 branch lines of free organs on the operculum (Fig. 22, d.o.L), 

 are innervated by a branch of the hyoideo-mandibularis facialis, 

 before the externus has separated from it. It leaves the main 

 trunk through the foramen at the base of the opercular 

 spine. 



Organs 8-1 1 are supplied by branches which pass from the 

 externus between the bony lamellae of the preoperculum to 

 the canal occupying the space between the outer edges of these 

 lamellae. Between organs 9 and 10 a branch is given off to 

 the three free organs forming the ventral line on the opercu- 

 lum (Fig. 22, V.O.I.). 



There are two free organs situated near the large pore which 

 marks the union of the opercular and mandibular portions 

 of the line, and which seem to correspond to the mandibular 

 pit line of Amia (Fig. 21, in.d.L), which are innervated by 

 branches from the externus. In the same way the two free 

 organs at the angle of the mouth in Batrachus may easily be 

 identified with the vertical cheek line in Amia (Fig. 21, c.L), 

 also supplied by a branch from the externus. 



The three canal organs of the mandible are innervated by 

 the externus, as also the four organs in the groove at the ante- 

 rior part of the mandible (Fig. 3), while the three superficial 

 organs in a line parallel with them are also supplied by a 

 branch of this same nerve (Fig. 22, ac.mdd). 



