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should be called the anterior meningeal artery. The small foramen 
between the alisphenoid and the orhitosphenoid bones through 
which the anterior meningeal enters the skull, apparently has been 
recognized by Jayne® alone. He figures it but does not describe it or 
name it. From the plexus there run a number of small vessels to the 
pterygoid, masseter, and temporal muscles. At the antero-lateral border 
of the plexus there are usually two branches larger than the other muscu- 
lar branches, that pass laterally between the orbit of the eye and the 
temporal muscle, and are distributed to the latter. , They seem to cor- 
respond to the A. temporalis profunda anterior of man. Tandler speaks 
of them as the deep temporal branches. I am unable to identify the 
bucco-labial vessel that Tandler says passes laterally from the plexus. 
Close to the origin of the deep temporal branches from the plexus 
there arises a branch that passes dorso-medially around the border of 
the structures in the orbit and enters the skull though the ethmoidal 
foramen in the frontal bone. In its course it gives off a lachrymal 
branch to the lachrymal gland and adjacent region, and a frontal branch 
to the region of the upper eyelid. This is evidently the vessel from 
the carotid plexus that Reighard and Jennings call the ophthalmic artery. 
But it does not supply all the structures in the orbit, very few muscles 
receiving vessels from it. Only in part does it correspond to the oph- 
thalmic artery of man. It were better named the ethmoidal, as its 
main portion is the ethmoidal artery. According to Tandler a common 
trunk arising from the internal maxillary artery divides into the lachry- 
mal, ethmoidal and frontal arteries. I find that this common vessel 
arises from the carotid plexus rather than from the main artery, but it 
is quite likely that the origin described by Tandler occurs sometimes. 
The muscles of the orbit for the most part receive their blood supply 
from small vessels of the plexus, but there seems to be no regularity in 
their arrangement. From the internal maxillary artery in the midst of 
the plexus there passes into the orbit a vessel of considerable size. This 
artery after a somewhat tortuous course through the plexus goes to the 
eyeball along with the optic nerve. It gives off a pair of arteries that 
enter -the eyeball at about the equator of the latter, and that evidently 
correspond to the long posterior ciliary arteries in man. Many other 
smaller short banches are given off to the posterior wall of the eyeball, 
and may be designated as the short posterior ciliary arteries, since they 
have the same general distribution as these latter arteries in man. The 
central artery of the retina enters the bulb along with the optic nerve, 
and is a very small vessel. This vessel supplying the eyeball is the 
ciliary artery. Tandler states that it arises from the carotid plexus. 
It may have such an origin occasionally, but in general it comes directly 
from the internal maxillary artery. Near the eyeball it is joined by one 
or two small vessels from the plexus. At about the same region there 
sometimes unites with it a vessel that emerges from the cranial cavity 
through the optic foramen. This latter vessel may be traced to the cir- 
cle of Willis a little posterior to the point of divergence of the anterior 
and median cerebral arteries. This vessel arising from the circle of 
6. Jaynes. Horace. Mammalian Anatomy, Part I, The Skeleton of the Cat. 
Philadelphia, 1898. 
