FISHES. 9 



derably arched, the ventral line horizontal to the anus, whence it slopes upwards to the 

 slender base of the caudal. The thickness is greatest at the gill-covers. The length, height, 

 and thickness of the head are equal to one another, and to rather less than one fourth of the 

 total length. Its shortness is owing to the vertical direction of the face, the front of the orbit 

 being nearly as far advanced as the lips. The eyes are lateral, the upper bony margins of the 

 orbits very prominent and uneven, presenting three irregular, angular corners. The anterior and 

 posterior frontal bones, which form the upper part of the orbit, have each their diverging ribs. 

 There is also a short longitudinal ridge on each elevated wall of the smooth mesial, inter- 

 orbital furrow. The whole space between the edges of the orbits is equal to a diameter of 

 the eye. The orbits are connected posteriorly by a slightly curved ridge, behind which there 

 is a deep transverse depression, that is bounded behind by the first dorsal spine, flanked 

 on each side by the conical eminences of the par-occipital s and temporal ridges. There is a 

 very small depressed cheek beneath the eye. The comparatively small preorbitar has an 

 elevated, ridged centre, from which a short three cornered point descends anteriorly, and a 

 slightly curved spine projects posteriorly. This spine reaches back to the middle of the eye. 

 The great suborbitar forms a conspicuous, prominent, very uneven ridge, which is not armed 

 with spinous points. The preopercular spine equals the preorbitar one in size ; immediately 

 beneath it, there is an acute angular point, and at some distance below a smaller point, the 

 under limb of the bone having but a slight inclination forwards. The small operculum is 

 situated almost wholly over the preopercular spine, and is furnished with two ridges, the 

 point of the upper one alone penetrating the skin. The gill-cover is attached by membrane 

 to the shoulder, but the curved gill-opening is ample, and runs forward beneath as far as the 

 fore end of the preoperculum and middle of the eye. The mouth is small, terminal, with a 

 slightly descending cleft, so that when the lower jaw is depressed it reaches rather farther 

 forward than the upper one. The rounded margins of the jaws are covered with microscopical, 

 densely crowded, close-shaven, villiform teeth. The vomer is prominent and apparently tooth- 

 less, and there are no teeth on the palate bones. The tongue is thick but pretty free. 



The skin is quite scaleless, and lax, and rather spongy. The lateral line runs in the 

 upper quarter of the height, and is formed of a series of short tubes. There are two conspi- 

 cuous fringed barbels attached to each limb of the lower jaw. There is also one attached to 

 the upper part of the eye springing from within the orbit, several skinny prominences on the 

 bony points of the head, and a row of round tufts on the second preorbitar ; numerous short 

 filaments are crowded at the tips of the dorsal spines, and a row at the base of the spinous 

 part of the fin is continued across the middle of the soft rays. There are also minute 

 filaments on the pectoral rays. The dorsal commences in the occipital notch. It is more 

 arched than the curve of the back. Its spines are tall and slender. The pectoral has three 

 detached rays beneath, which curve downwards. The ventral spine is slender and shorter 

 than the soft rays which are all forked : the last one is attached by membrane to the belly 

 for its whole length. Only two anal spines could be detected without dissection, but there 

 may be another small one hidden under the skin. 



