OF THE MARSIPOBRANCH FISHES. 
391 
The supra-lingual ( s.l.c.) is cut through where the hard hinder bars run into soft 
cartilage above; the upper plate is narrow; the basi-hyal (b.hyP.) like the last. 
Section 21 (Plate 13, fig. 4).—This section was made through the second fenestra, 
the trabeculae (tr.) are cut across, and the pedicle (pd. ) in its hind part; the descending 
pterygo-quadrate bar (pg.) is cut through much further down. The naso-palatine 
canal ( p.n.c .) is squarish, and the folds of its lining membrane are shown; under it 
is the fast narrowing intertrabecula ( p.i.tr .). Here the elbow of each hard hind bar 
of the supra-lingual (Plate 12, fig. 8) is cut across outside one of the hinder teeth. 
The basi-hyal ( b.hy p .) is now in two pieces, below. 
Section 22 (Plate 13, fig. 5).—This section is between the pedicle and the head of 
the hyomandibular, across the manclibulo-hyoid band (m.hy.) and the mandibulo- 
hyoid fenestra (m.h.f) above, and through the quadrate (q.) below ; the space between 
these bars is the second lateral fenestra (Plates 9, 10, l.f 2 .). Inside the upper bar 
the front face of the auditory capsule (cm.) is shaved off; these organs are confluent 
with the narrow fore part of the parachorclals (Plate 10, figs. 1-3, au., iv.), where the 
trabeculae begin in front of the notochord ; the intertrabecula ( p.i.tr .) is very narrow 
here over the square naso-palatine canal 1 (p.n.c.). One of the hinder cheek-teeth is 
1 cut through on each side, and part of the cartilaginous wall and the two hind snags. 
The narrowing hinder basi-hyals (b.hy p .) are distinct. 
Section 23 (Plate 13, fig. 6).—If this section be compared with the dissections 
(Plates 9 and 10) the great conformity of the two kinds of preparations will be seen. 
This and the next are the last sections in front of the notochord ; the moieties of the 
investing mass, or paracliordals, form here a mere lip to the lower edge of the 
auditory shell (au.), which is seen to be reniform in section, and membranous 
within, the walls being thickish, and composed of hard cartilage. Here the tip of the 
bowl of the intertrabecula (p.i.tr.) is perforated, and thus it is seen in section as two 
points of soft cartilage over the square naso-palatine canal {p.n.c.). 
The mandibulo-hyoid bar (m.hy.) is a small oval section, a considerable distance 
from the capsule ; much further down there is a curious hook of hard cartilage, and 
below it, but nearer to it, on the outside, another oval section. The hook is the first 
pharyngo-branchial (p.br 1 .), at its enlarged end, where it partly occludes the second 
ifenestra (Plates 9 and 10), and the bar below is the narrow neck where the pterygoid 
passes into the quadrate (cp), under the second fenestra. The basi-hyal (b.hy p .) is 
like that of the last section. 
Section 24 (Plate 14, fig. 1).—This section sheds light upon the dissections, and is 
also in turn explained by them.* Here, as in the last, the paracliordals are very 
* I must here repeat the fact that these sections show the cartilage to be hard, in places where in the 
dissections it was soft, on account of the greater age of the specimen made into sections ; where any other 
apparent want of conformity exists between the two sets of observations, it is due to compression of the 
specimen m cutting, for my best specimens were not well preserved, and at the best the pharynx and its 
velum, are very elastic and mobile. 
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