Dr. A. Smith Woodward—Fossil Fishes from Egypt. 403 
can be readily identified (Fig. 1a). Below the base of the skull (c.) 
the pterygo-quadrate arcade is seen, the ectopterygoid having a 
thickened and sharply bent oral margin, and the relatively large 
quadrate (quw.) inclined forwards. The long and gently arched 
maxilla (mx.) has a large articular head in front and is slightly 
expanded at its hinder end. The slender, parallel premaxilla (pmz.) 
completely excludes this bone from the margin of the mouth. The 
mandibular ramus is short and deep, triangular in shape, with the 
dentary (d.) and articulo-angular (ag.) taking about equal shares 
in its constitution. The only teeth clearly distinguishable are very 
minute points on the oral border of the dentary. The pre-operculum 
(pop.) is sharply bent, with the upper and lower limbs of equal size, 
each tapering to a point. Its hinder border is rounded at the angle, 
and its smooth outer face is marked with four large openings into the 
slime-canal. he small operculum and sub-operculum are somewhat 
displaced, and there are traces of about six branchiostegal rays below. 
Nine vertebre can be counted in the abdominal region, and two of 
the centra exhibit the lateral median longitudinal ridge. The minute 
ribs cannot be seen, but the large hypapophyses are conspicuous below 
the six posterior centra, slightly i increasing in size backwards. There 
are twenty-two caudal vertebre, and the neural and hemal arches are 
long and'slender. The hindmost caudal centrum bears the complex 
of hemal and neural arches for the support of the caudal fin shown in 
Fig. 16. The long and slender left clavicle is well seen (Fig. 1a, cl.), 
bent forwards at its upper end, slightly expanded below, and there 
are traces of the pair of small rod-shaped pelvic fin-supports (plv.) 
among the scales postero-inferiorly. The rays of the paired fins are 
not recognizable with certainty, but the anal and caudal are well 
displayed, and the hinder part of the dorsal is also seen. The rays 
of the anal and dorsal fins are remarkably slender, and those of the 
anal are thirty-six or thirty-seven in number. The foremost anal 
fin-support is a long curved bone forming the hinder border of the 
abdominal cavity. The caudal fin, which is rounded, comprises about 
eighteen rays, of which the first three at the origin above and below 
are short and comparatively stout, closely adpressed and gradually 
increasing in length. The principal caudal fin-rays are distantly 
articulated and bifurcate distally. The trunk is completely covered 
with a dense squamation, which seems to extend slightly over the 
base of the dorsal and anal fins. Though not easily observable, the 
scales are evidently antero-posteriorly elongated, and there are some- 
times traces of a fringe of slender denticulations at their hinder 
border. 
As already suggested, the fish now described is most closely similar 
to the small Solea kirchbergana trom the Lower Miocene of Wirtemberg, 
and, like that species, it appears to differ only from the typical 
existing Solea in the comparative shortness of ‘its caudal region. 
In the latter respect it corresponds with the allied existing genus 
Achirus, which has curiously modified pelvic fins.’ As, however, the 
’ D.S. Jordan & D. K. Goss, ‘A Review of the Flounders and Soles (Pleuro- 
nectidze) of America and Europe’’: Ann. Rep. U.S. Fish. Comm. for 1886 (1889), 
p. 308. 
