84 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
almost immediately and the lungs are very richly supplied. The 
branches to the heart did not appear. ) 
Ramus recurrens laryngis X (Plate 2, fig. 5; rer. X.). The course 
of this ramus is directly cephalad to the larynx, following along the — 
lateral side of trachea to reach it. Numerous very fine branches are 
given off in its course (not shown in Plate 2, fig. 5). Reaching the 
larynx this nerve breaks up, first dividing into the two main terminal 
divisions shown in the figure. One of these lies on the dorso-lateral 
side of the larynx and passes through a portion of the longitudinal 
muscle to reach a more anterior position, where it innervates the 
mucous membrane just posterior to the glottis. The other branch, 
the more median one in the figure, innervates the mucous membrane 
of the ventro-lateral part of the larynx. The first branch in its pas- 
sage through the muscle becomes/closely involved in the motor com- 
plex, and is separable from it only through the study of sections. 
If it contributes motor fibers to this, it is only very slightly, and my 
belief is that in Anolis the ramus recurrens is wholly sensory. See- 
tion 659 (Plate 4, fig. 11) is anterior to the main branches so that no 
part of the recurrent ramus appears. Some motor twigs are shown 
in the muscle. 
More data are needed to homologize the branches of nerves [X and 
X with those of Amphibia. In the latter the ramus recurrens X in- 
nervates the muscles of the larynx (Coghill, :02, p. 245; Norris, :08, 
p. 552). 
Through comparative anatomy Fischer arrived at conclusions whieh 
conform with the facts as stated for Anolis. He found the intimate 
mingling of the terminal twigs of the ramus recurrens X and the 
pharyngo-laryngeus, so generally described in other forms, to be 
absent in two cases, so that the distribution of the two nerves was 
distinct, and in these cases the recurrent ramus is held to be sensory, 
not motor. “In den Fallen, wo der R. recurrens sich nicht mit jenem — 
[pharyngo-laryngeus| verbindet (Varanus Bengalensis, Platydactylus — 
guttatus) geht dieser [r. recurrens] nicht in die Muskeln, sondern an - 
die Schleimhiiute des Kehlkopfes” (Fischer ’52, p. 48). But Watkin- 
son (:06, p. 467) for another species of Varanus states that the united 
fibers of the ramus recurrens X and the terminal branches of 1X. 
are distributed to the muscles of the larynx. Her observation was not 
properly supported, however, in regard to either point, as im her 
species (1) nerve IX previously received fibers from X, as in Anolis, 
and (2) a mere union of rami as demonstrated in dissection does not 
in itself prove similarity of distribution. | 
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