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special levator muscles, noticed both by Cuvier and by Professor 
Owen, in the possession of which the Tapir again resembles the 
Horse, the muscles of this organ are arranged upon the usual type. 
Their fibres radiate from a point just before the eye, some running 
backwards to form the orbicularis palpebrarum ;' others spreading 
upwards to the top of the proboscis, forming the compressor nasi ; 
others proceeding downwards and forwards, to constitute the levator 
labii superioris alzeque nasi. The depressor of the proboscis, and the 
orbicularis oris, are well developed, the latter muscle being very thick, 
especially in the under lip. 
I have yet seen nothing to shake my opinion, that the structure of 
the larynx will one day become of great importance to the zoologist, 
although at present my opportunities have been far from sufficient to 
enable me to point out which peculiarities in its formation are truly 
characteristic of certain groups. In this case, therefore, I limit myself 
to the comparison of it with such as my collection possesses, namely 
with that of the Horse, as a near ally, and with those of the Peceary 
and the Sheep, as members of the other great Ungulate division. 
The os hyoides has the characters usual in the order ; its stylohyal 
pieces agree with those of the Horse in being very narrow at their 
junction with the lesser cornua, and gradually widening, the reverse 
being the case in the Peccary and the Sheep. The latter animal, 
however, like most ruminants, has an intermediate piece at the junc- 
tion of the stylohyal and the lesser cornu. The Tapir wants the 
sudden expansion of the upper end of the stylohyal, which is common 
in the Ungulata, and differs remarkably from the Horse in the small 
development of the true basihyal, and in the total absence of the 
strong epihyal process. The thyroid cartilage, however, agrees pre- 
cisely with that of the Horse in the great obliquity of its alz, in its 
median portion being much thickened above, and very deeply emar- 
ginated below ; the Peccary and the Sheep presenting the reverse of 
each of these characters. The cricoid and arytenoid cartilages do not 
present any essential points of difference; but in the Peccary the 
cricoid is very peculiar in having its anterior part drawn down, so as 
to encroach upon four of the tracheal rings, and deeply emarginated 
above. In the interior of the larynx the Tapir has the superior and 
inferior ligaments well-marked, though not very prominent ; the 
latter, or chordz vocales, are slight, but sharp, folds in the mucous 
membrane ; the former are thickened anteriorly. Just at the base 
of the epiglottis is a pair of arched openings, each leading into a small 
sinus, which extends upwards beneath the base of the epiglottis and 
inward thickening of the thyroid cartilage, and downwards in front 
of the anterior attachments of the superior ligaments. The Horse 
has, like the Tapir, a fossa excavated in the thickened upper part of 
the thyroid cartilage ; and it would appear from Cuvier’s remarks 
(who, however, had but a drawing to inspect), that the Rhinoceros 
has something similar. The Tapir entirely wants the lateral sacs 
observable in the Horse. 
The muscles of this organ are arranged as usual. The homologues 
of the sternohyoid and sternothyroid muscles arise, as in some other 
