DEVELOPMENT OP THE SKULL IN THE BATRACHIA. 
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above (fig. 8), in the groove on tire outer edge of the pterygoid. Also it forms a large 
oval condyle which fits on a shallow facet on the front of the ear-capsule (fig. 9, pel.) 
The outer fork, or quadrate “pier,” reaches but little further back (fig. 9), but is of 
great length when seen from the side (fig. 10); its condyle (figs. 9 and 10, q.c.) are 
large, convexo-concave, and reniform. 
In descending, the quadrate pier is curved like a half-bent knee; its splint, the 
squamosal (sq.) fits to this bend; the hinder (inner) lobe of the condyle is higher than 
the other. The pedicle (pel.) grows inwards exactly half as far as it did in the Tadpole; 
the fixed band, from the foramen ovale to the enlarged part which becomes the condyle, 
has all been absorbed. 
The quadrate (fig. 9) above the condyle is only slightly ossified by the quadrato-jugal. 
The annulus (ct.ty.) is an open crescent; it is broad, and its front horn is higher 
than the other ; its size is normal. The Eustachian ( eu.) tube is small—half the normal 
size, and circular; the cavity altogether is very limited. The stapes (figs. 8, 10, 12) 
is very large, long-oval, with two anterior emarginations, and but little bossed. The 
columella, altogether, is relatively as large as its morphological counterpart in the 
Skate, viz.: the “hyomandibular.” 
The inter-stapedial (fig. 12, i.st.) is a short sub-oval segment of cartilage; the 
medio-stapedial ( m.st.) is a long rod of bone, thick and clubbed, proximally ; the 
supra-stapedial (s.st.) is a bud of cartilage growing from the upper edge of the short- 
stalked, peltate extra-stapedial ( e.st .). 
The mandible (fig. 10) is curved more than usual; its mento-Meckelian element 
(m.mk.) is unusually large, showing that metamorphosis did not lessen the actual size 
of the lower labials. 
The stylo-hyal (fig. 9, st.h.) is continuous with the small tract of unossified cartilage 
at the outer part of the auditory region. The cerato-hyal (fig. 11, c.liy.) is rather 
broad, and turning back, as ahypo-hyal (h.hy.), without a lobe, it partly splits into two 
bands, a hyoid and “ extra-hyal,” as in some other kinds. 
The notch of the basal plate is deep and the plate itself ( Ij.h.br .) rather shorter than 
usual, and swollen. The fore lateral lobe is very large, and crenate in front; the hind lobe 
is normal, but outstanding. The thryo-hyals (t.hy.) are long and rather flat; between 
these roots there is a thick pentagonal wedge of bone—a “ basi-branchial ” ( b.br 1 .). 
The investing bones are similar, as to thickness and strength, to those of the 
larger “ Ilankke ” and “ Polypedatidse of the same region. 
The fronto-parietals (figs. 8, 10, f.p.) are very short and broad ; their interorbital 
region forms, together, a square, with a small projection on each side, near the front; 
they are bevelled behind, as they pass into the expanded temporal region. Here, and 
over the fore half of the hind skull, they are modelled most accurately on to the endo- 
cranium, have rounded ends, and also are wrought into a rounded, low, transverse 
crest on each side. 
In front these bones are scant where the ethmoidal wings grow out ; they touch the 
