MUSCLES INNERVATED BY THE FIFTH CRANIAL NERVE. 595 
pterygoid, teusor veli palatini, tensor tympani, mylohyoid, 
and anterior belly of digastric. 
Though the innervation of the tensor veli palatini — both in 
man and in other mammals — by the fifth nerve has been 
described by anatomists, the evidence afforded by cases of 
disease and by division of the roots of the nerve in man is 
equivocal. Krause found no anomalies in the position of the 
palate after extirpation of the Gasserian ganglion and division 
of the motor root. Cushing found a marked asymmetry of 
the palate in four cases, and elicited movements of the palate 
by electrical stimulation of the peripheral stump of the fifth 
nerve in one case. Davies found asymmetry of the palate in 
five, and no asymmetry in twenty-oue, of twenty-six cases 
operated on by Hoi’sley ; and he records that in three cases 
Horsley stimulated the peripheral end of the divided 'fifth 
nerve without any movement of the palate resulting. Davies 
concluded that “the balance of evidence seems to show that 
the fifth nerve has nothing to do with the innervation of 
the palatal muscles.^’ 
Beevor and Horsley (’88) stated that iuMacacus sinicus 
movements of the palate occurred on intra-cranial stimu- 
lation of the vago-accessorius, but did not occur on intra- 
cranial stimulation of the seventh nerve. They did not state 
whether movements of the palate did or did not occur on 
intra-cranial stimulation of the fifth nerve. 
Davies further states that “ no change has been observed 
to follow excision of the Gasserian ganglion, either in the 
tenseness of the drum or the increased power of the indi- 
vidual, when tested with a Gallon whistle, to appreciate 
high-pitched sound,” and consequently discards the innerva- 
tion of the tensor tympani by the fifth nerve. 
To obtain additional information on these mattei’S Sir 
Victor Horsley was good enough, at my request, to divide 
the roots of the fifth cranial nerve proximal to the Gasserian ' 
gauglion in two monkeys (Macacus cynomolgus). The 
wounds healed by first intention. The animals Avere allowed 
to live for thirty days, and then killed by an overdose of 
