No. 3.] WZUSCLES AND NERVES IN AMIA CALVA. 619 
passes dorsal to and behind the interhyal, dorsal to or across 
the upper end of the ceratohyal, and then downward and for- 
ward along the inner surface of the branchiostegal rays, lying 
immediately behind the posterior edge of the ceratohyal. On 
reaching the fourth or third ray from in front, it anastomoses 
completely with the r. ghs trigemini as already described. 
During its course along the inner surface of the gill-cover a 
large branch is sent backward along the lower edge of the 
operculum, another along the lower edge of the sub-operculum, 
and others, irregularly distributed, along the inner surface of 
the interoperculum, the inner surface of the branchiostegal 
rays, and the outer surface of both divisions of the hyohyoi- 
deus, which muscle they supply. 
The r. palatinus facialis (ff) arises from the ventral surface 
of the trigemino-facial ganglion toward its median edge. It 
runs downward and forward in the upper, lateral chamber of 
the eye-muscle canal, and, passing through the palatine foramen, 
enters the palatine canal between the parasphenoid and the 
ventral surface of the cartilaginous cranium. There it turns 
forward and separates into two parts, the r. palatinus anterior 
facialis (faf) and the r. palatinus posterior facialis (pff). The 
latter turns outward and forward through the foramen palatini 
posterioris facialis, immediately in front of the anterior edge of 
the lateral wing of the parasphenoid, passes immediately ven- 
tral to the efferent pseudobranchial artery, crosses the space 
between the lateral edge of the parasphenoid and the median, 
dorsal edge of the palato-quadrate arch and reaches the dorsal 
surface of the entopterygoid (Z/VP, Fig. 2, Pl. XX). Along 
the outer, dorsal surface of that bone it runs downward, out- 
ward, and forward to the edge of the cartilaginous palato-quad- 
rate (fg), under which it passes, then under the posterior edge 
of what van Wijhe calls the autopalatinum (4 UP), and onward 
to the lateral edge of that bone, either coming to the upper 
surface of the bone through a foramen near its hind edge and 
then lying on that upper surface, or continuing downward to 
the edge of the bone between it and the dermopalatinum (DP), 
The nerve then passes beyond the lateral edge of the palatine, 
and lying in the thick upper lip, turns forward, sends anasto- 
