WILLARD: CRANIAL NERVES OF ANOLIS CAROLINENSIS. 97 
tiles: (1) the persistence of three occipital foramina, and (2) the mixed 
spinal and hypoglossal character of its third root. The latter condi- 
tion is not described for any other lizard. There is practically no 
union of the hypoglossal part of the last root of XII with the first 
spinal nerve, a condition which is described by Fischer as general. If 
we imagine the cephalization process to progress further in Anolis, we 
should expect roots one and two of XII to merge with each other, the 
spinal or cervical part of root three to disappear and the first spinal 
nerve to be drawn more into the field occupied by it. This is practi- 
eally what is represented (Fischer) in those forms where but two roots 
have been described. Evidence from the embryological side (Van 
Wijhe, ’86, Van Bemmelen, ’89, Hoffmann, ’79-90) supports Fiir- 
bringer’s (’97) generalization that the hypoglossal of reptiles repre- 
sents three ventral spinal roots. 
The cervical plexus is represented in Anolis by the combination of 
XII with the first spinal and the commissure between the second and 
third spinal nerves. The ventral ramus of the first spinal is but 
loosely associated, sometimes not at all, with XII. The only constant 
connection, then, is that of the dorsal ramus of XII (cervicalis dorsalis 
XII) with the same ramus of the first spinal (Fig. 6, crv. d. XII). 
|This anastomosis may be considered a remnant.of the closer rela- 
tion of these nerves which existed before the rise of the tongue mus- 
culature. 
Anolis agrees with the typical condition of reptiles in the absence of a 
sensory component in the first and second spinal nerves. Fischer’s 
reference to the exceptional occurrence of a dorsal root for the second 
‘spinal is not carried farther in his descriptions. Rabl-Riickhard 
ms p. 342) states that in the alligator the third is the first of the spinal 
ee 
herves to possess a sensory part, but in contrast to the lizards (Anolis) 
he third and fourth spinal nerves also have (Fischer) greatly redueed 
lorsal roots, indicating a less sensitive integument in the alligator. 
. t will be seen that in Anolis the field innervated by the sensory com- 
ponents of the third spinal nerve extends far cephalad both on the 
‘orsal and ventral sides, thus demanding a strong dorsal root. 
| Inregard to the second point in the comparison, i. e., the differentia- 
jon of the nerve itself, we have to deal with a histological problem 
ich cannot be profitably discussed without a complete knowledge of 
“ne histological elements involved. The fixation of my material is 
ot uniform enough in all parts to admit of a detailed comparison of the 
thber of the medullated fibers as found in different nerves. How- 
rer, in Anolis the difference in the fibers of XII, as compared with 
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