‘ 
A 
‘? WILLARD: CRANIAL NERVES OF ANOLIS CAROLINENSIS. 91 
margin by passing around the genioglossus muscle (Plate 4, fig. 10, 
Ing. 1. XII*). The other division (ing. 1. XII?) of the lateralis XII 
combines with lingual V and the two mingled components are dis- 
tributed together (Plate 2, fig. 5). “The dorsal musculature of the 
tongue begins here to take on the crossed arrangement of its fibres 
(p. 35), and this seems to be related to the presence of papillae on the 
surface characteristic of the anterior end of the tongue (Plate 4, fig. 9). 
In the distribution of the three main divisions of XII, it is important 
to note how each is quite definitely limited to a particular part of the 
musculature, and that the part of XIJ which is mingled with V inner- 
vates only the strictly intrinsic musculature, for the most part those 
short muscle fibers which are inserted into the mucous membrane of 
the papillae-bearing dorsal surface. 
These papillae deserve special study because of certain peculiari- 
ties in their finer structure. These conditions were in part brought 
out in the unstained material. The muscle fibers, which show a high 
degree of differentiation between the light and dark transverse bands, 
extend all the way to the tip of the papillae, and medullated nerve 
fibers could also be followed the same distance. Inasmuch as these 
somatic motor and general cutaneous fibers are approximately of the 
same size, it is not possible to distinguish between them by this 
criterion. It is fair to assume, however, that the fibers at the ends of 
the papillae are sensory, for, from what we know of the innervation 
of striated muscle, it is not to be expected that the muscle fibers are 
innervated at their scattered distal ends rather than at a more proximal 
poimt, where they are closer together and nearer the source of nerve 
supply. We know also that nerve fibers of the general cutaneous 
type have come into this region in the lingual branch of ramus maxil- 
laris VY, and presumably they must reach the surface. No taste buds 
| were found among these papillae, although at the sides of the tongue 
| such buds were found among the tubular glands.!_ In a region where 
| these papillae are best developed they are flattened at the end, where 
| the epithelium is of the stratified columnar type. The sides are cov- 
ered with simple glandular epithelium. The flattened ends show 
| many cells extending out as though protruding individually. The 
free ends, being knob-like, contain the nuclei, while the base is attenu- 
ated into a slender column. The result is a sort of tuft of knobbed 
| projections forming the end of each papilla. It is to this flattened 
} terminal portion that the muscle and nerve fibers pass. 
4 
‘Later study on the histology of the tongue has disclosed a few papillae 
bearing single taste buds in their flattened ends. 
