854 MR. ST. GEORGE MIVART ON THE [Dec. 6, 
mass which arises from the basihyal within the cup-like cartilagi- 
nous expansion of the lower end of the anterior cornu. Passing 
upwards in front of and within the posterior cornu, it is inserted 
into the summit of the latter. 
A muscle, which can only improperly be termed the genio-glossus, 
(fig. 7, G. G.), springs from the inside of the anterior part of the 
mandible, but posterior to the origin of the cerato-mandibular. 
Passing backwards, it meets its fellow of the opposite side at the 
hinder end of the dorsum of the tongue. 
Sterno-hyoid* (figs. 1, 3, 6, and 7, S. H). This arises from the 
sternum, between the sternal ends of the second and third sternal 
ribs, coming out, as it were, from a little muscular pouch formed on 
the inner side by the anterior end of the rectus, and on the outer 
side by fibres of the internal oblique, or external intercostals. Passing 
forwards and broadening, it is inserted into fascia closely connected 
with the ventral surface of the basihyal, opposite the insertion of 
the genio-hyoid. 
The sterno-thyroidy (figs. 6 and 7, T. H.) springs from the 
sternum, and, expanding anteriorly, is inserted into the summit of 
the thyro-hyal. As it passes forward it is embraced externally by 
the omo-hyoid, which dips in between it and the sterno-mastoid. 
Omo-hyoidt. This is an exceedingly slender and delicate muscle 
(figs. 6, 7, and 13, O. H.), which is so bent upon itself that, while 
its hyoidean portion runs upward and forward, its scapular part 
runs upward and backward, the bend taking place where it passes 
beneath the sterno-mastoid. The muscle is thus an elevator of the 
hyoid, instead of, as is generally the case, a protractor. 
It springs from the upper anterior part of the basihyal, close to 
the insertion of the sterno-hyoid. Passing upward outside the 
sterno-thyroid, it dips in between the latter and the sterno-mastoid. 
It then passes superficially to the deltoids and lower part of levator 
claviculz, and is finally inserted into the outer surface of the scapula, 
just between the summit of the anterior suprascapular and the insertion 
of the levator claviculz. 
III. Muscies or THE TRUNK. 
Longissimus dorsi (figs. } and 2, L’ and LZ’). This muscle is 
exceedingly large in Parson’s Chameleon, much larger, relatively as 
well as absolutely, than in the common Chameleon. ‘The large 
development of this muscle might be anticipated from an examination 
of the skeleton ; for not’ only are the neural spines much prolonged, 
but the articular processes (zygapophyses) are so produced as to 
simulate (if they are not rather homologous with) the metapophyses 
of the Mammalia. 
This large muscular mass is pretty clearly divisible into a larger 
upper and a smaller inferior portion. 
* Cuvier, J. c. p. 582; Meckel, 7. c. p. 186. 
+ Cuvier, J. ¢. p. 532; Meckel, 7. ¢. p. 136. 
{ Cuvier, 7. c. p. 532; Meckel, 7. c. p. 136. 
