94 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
lateral part (spv. l. 3), which divides at once into several small rami, 
innervating the muscles immediately adjacent and caudad to it. 
The dorsal ramus (spr. d. 3) divides into two branches; the one, 
wholly motor (Plate 2, fig. 6), passes dorso-mesad to supply the muscle 
lyi ing against the neural arch; the other, a mixed sensory-motor, re- 
ceives a communicating branch from the dorsal ramus of the second 
spinal nerve and innervates the most dorsal portion of the longissimus 
muscle anterior to the general position of the nerve as a whole (Plates 2, 
3, figs. 4, 6). The cutaneous part passes through this muscle to the 
skin, where it divides to be distributed both dorsally and laterally; 
but like the motor part its field of distribution is chiefly anterior to 
the nerve. 
The ventral ramus is a combination of the ventral divisions of the 
motor and sensory components. The mixed branch thus formed 
passes ventro-laterad between the m. longissimus colli and spinalis 
colli (Plate 7, fig. 24, spr. v.3). It crosses on the dorsal side of ramus 
visceralis X and the sympathetic trunk (Plate 2, fig. 4). Between 
the muscles above mentioned it receives a reinforcement of motor 
fibers from the ventral ramus of the second spinal nerve (Plate 7, 
fig. 24, spr. v. 2), about half of whose fibers join the third spinal for 
distribution, the rest continuing caudad. This combined ventral 
ramus now passes laterad into m. capiti-cleido-episternalis. Here the 
motor elements leave the main ramus to supply this muscle in both 
caudal and rostral directions. (The motor fibers appearing in m. 
depressor mandibulae adjacent to this region are found by dissection 
to come from ramus hyoideus VII). The cutaneous components 
also divide into two branches (Plate 2, fig. 4). One passes ventrad 
between mm. cucullaris and depressor mandibulae, the other passes 
directly through the latter muscle to a position just lateral to the 
main trunk of nerve XII, where it turns cephalad to be distributed 
to the integument along the ventro-lateral region of the neck and 
throat (Plates 3, 1; figs: 6,:23, spi. v.-8): 
A variation in the ganglion of the third spinal nerve deserves men- 
tion in this connection. This is indicated in the plotting and consists 
of a small group of ganglion cells on the dorsal sensory ramus not far 
from the main ganglion. In the labelling a dotted line runs to this as 
well as to the main ganglion from the letters (gn. spi. 3). In other, 
series of sections of Anolis this small ganglion did not appear. The 
size of its cells and its nerve connections do not suggest for it a sym: 
pathetic function, the cells being in every way similar to spinal gat 
glion cells, their position probably being due to a migration 0 
some of these cells from the main ganglion. 
