Drxon—On the Development of the Branches of the Fifth Cranial Nerve in Man. 53 
when they end. Their terminations are 0°8 mm. apart. The temporal, as we 
have seen above (p. 27), communicates with the lachrymal branch of ophthalmic. 
The course of the two branches to Meckel’s ganglion is obliquely inwards and 
forwards. 
The superior maxillary nerve, having given off these branches, passes almost 
horizontally forwards, describing however, a very gentle curve, the convexity of 
which looks downwards. In this part of its course, the nerve gives off two fine 
branches, not more than 0-2 mm. in length, which pass downwards and forwards, 
but do not quite reach the roof of the mouth. These two branches which are not 
shown in the figures possibly represent the posterior and middle superior dental 
nerves of the adult. In front of these two nerves, a larger branch takes origin 
from the superior maxillary, which at first turns downwards and forwards, and 
then runs inwards, above the roof of the mouth, just behind its anterior border. 
This last nerve gives off fine branches which come near to the ‘“ Zahnleiste.” This 
nerve probably represents the anterior superior dental of the adult. Soon after 
this last nerve is given off, the whole superior maxillary breaks up into a series of 
branches, which radiate from one another, some turning inwards, some inwards 
and upwards, and others inwards and downwards. A few fibres pass outwards 
and come very near to, if they do not actually communicate with, branches of the 
facial nerve. 
IF’. M.—Length of superior maxillary to final breaking up = 2-0 mm. 
Temporal branch : : : : : = 0°38 mm. 
Malar branch : 5 : : : : = 08 mm. 
Anterior superior dental : ; : : = 0:9 mm. 
Meckel’s ganglion is placed to the inner side of the superior maxillary nerve, its 
upper border corresponding to the level of this nerve. The ganglion measures 
from side to side 0-4 mm., and from before, backwards, and downwards (its longest 
diameter) 0°6 mm. (fig. 10, Plate I.). The ganglion is placed close to the anterior 
and inner surface, of the block of cartilage, which separates the second and third 
divisions, of the fifth nerve, near their origins. From the outermost part of the 
ganglion, a curved horn-like projection passes round the upper surface of this 
cartilage, towards the Gasserian ganglion, from which, however, it is separated 
by a blood sinus. This horn-like process comes near to, and seems to communicate 
with, a somewhat similar process of the otic ganglion, which curves round the 
under and posterior aspect of the same cartilage. 
The exact limits of the ganglion are not easily determined at all points, but 
it has a sharply defined lower and anterior surface, from which some fine branches 
come off, the probable representatives of the descending palatine branches of the 
adult. The fibres to form these descending palatine nerves can be traced through 
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