No. 3.] MUSCLES AND NERVES IN AMIA CALVA. 497 
the internal carotid canal, the palatine canal lodges the anterior 
branch of the palatinus facialis, the pharyngeal branch of the 
glossopharyngeus and a small branch only of the internal carotid. 
2. Carotid Arteries, Hypophysis Cerebri, and Saccus Vasculosus. 
The carotid arteries in the young of Amia have been described 
by Wright (No. 133, p. 494). With the results obtained by 
him, my work both on the young and on the adult is mainly, 
but not entirely, in accord. 
The efferent artery of the first branchial arch (ea. I, Fig. 28, 
Pl. XXV, and Figs. 61-63, Pls. XXXVI and XXXVII) as it 
bends inward and backward to join the dorsal aorta, gives off two 
vessels, the common carotid artery (cc) directed forward, and the 
hyo-opercularis (Zo) directed forward and outward. From near 
the root of this last artery a small branch is sent backward and 
upward, the remaining and larger portion of the artery continu- 
ing forward and outward until it reaches the facial foramen, 
which it crosses under the issuing truncus hyoideo-mandibularis 
facialis. It then turns upward, outward, and backward above 
the nerve, and running backward above the adductor hyoman- 
dibularis, separates into two main parts, the hyoid and opercular 
arteries. The former joins and accompanies the truncus hyoi- 
deo-mandibularis facialis and its branches ; the latter, destined 
to supply the inner surface of the operculum, separates into 
two parts, one of which runs backward above, and the other 
backward and downward below, the opercular process of the 
hyomandibular. As the main hyo-opercularis artery passes 
forward across the facial foramen, under the facialis, it sends a 
branch upward in front of that nerve, through the foramen into 
the upper, lateral chamber of the eye-muscle canal. Branches 
are there given to tissues in the canal, and the artery then, 
running upward and forward lateral to the trigemino-facial 
ganglion, issues through the trigeminal foramen with the ramus 
buccalis facialis and truncus maxillaris trigemini, which nerves 
it accompanies in their further outward course. No branches 
could be definitely traced into the cranial cavity proper or the 
auditory labyrinth, as described by Wright (No. 133, p. 495). 
