the soft palate partly overlie the posterior teeth of the 

 vomer, which is the cause of the artist having reprcseuted, 

 in fig. 8, the dental surface as tapering more towards the 

 gullet than it actually does. Palatine teeth smaller than the 

 nasal ones, not quite so flat on the crown.s, and disposed 

 so as to form an elliptical dental plate, which has also been 

 dran'n in figure 8 as tapering too much, owing to the pout- 

 ing of the lips. There are six or seven teeth abreast in 

 the widest part of the plate, and two or three posteriorly. 

 The dental plates on the limbs of the lower jaw contain 

 about five teeth in the middle, and taper off gradually to- 

 wards the corner of the moutli. They are separated from 

 one another at the symphysis by a smooth line. The up- 

 per jaw projects so much beyond the mandible, that the 

 whole nasal disk is anterior to the tip of the latter ; and 

 when the mouth is closed, the convex dental surface of the 

 fore end of the mandible applies to the anterior vomerine 

 teeth, which correspond with them in size, and are larger 

 than the other teeth. 



The head is conical, the snout small and acute, with a 

 thick short tubular nostril on each side of it, but a little 

 posterior to the extreme tip, and having an inclination 

 downwards. The posterior nostril is under the eye, rather 

 on the inner border of the lip, and is covered by a valve 

 which gives a downward aspect to the opening. A small 

 acute papilla overlies a minute notch on the edge of the 

 lip, between the nasal openings of each side, and behind 

 the posterior nostril there exists a more minute papilla, all 

 of which contribute to give a character to the orifice of the 

 mouth different from that of Aiiguilla or Miirwna. The 

 eye is rather small. There are four conspicuous pores on 

 each limb of the mandible, several on the under lip, and 

 three on each side of the snout above and before the eye. 

 The nape and throat, being elastic, bulge out, and are the 

 thickest parts of the fish : they are marked on each side 

 by about twenty-four fine longitudinal furrows, which run 

 back to the gill-openings. The elasticity of these parts is 

 maintained by thirty-three gill-rays, which spring from 

 each branch of the os liyoides : they are as fine as horse 

 hairs, and are very curiously arranged in two layers. The 

 rays of the left branch make an abrupt curve across the 

 throat, and then return to circle round the left operculum 

 to the nape. On the right side, the twenty uppermost or 

 posterior rays run ventrad of the left rays, curving more 

 than half-way across the throat, and returning over the oper- 

 culum to the right side of the nape; while the thirteen an- 

 terior ones sweep at once to the left side, in contact with 

 the left gill-sac, and consequently above or dorsad of the 

 rays which spring from the left branch ; they then curve 

 backwards across the throat to the right side, where they 

 protrude a little from beneath the edge of the other rays. 



Gill-openings wider than those of Miir(cmt, and lower 

 down, being similar in appearance to those of AiiguiUa. 

 Branchia; four, with five openings at their bases into the 

 gullet. Pharyngeal bones armed with acute teeth. Heart 

 posterior to the branchiae, and placed between the hinder 

 lips of the gill-openings. The humeral arch is composed 

 of two slender bones on each side, which do not meet 

 their fellows on the ventral line. Pectoral fin oval, of mo- 

 derate size, sustained by sixteen branching rays. 



Body nearly cylindrical, the back carrying its roundness 

 far past the anus, and the tail, which is more compressed 

 towards the tip, retaining its lateral convexity, its extreme 

 tip being conical. The dorsal commences just behind the 

 base of the pectoral, and carries its width well down the 

 tail, as does also the anal. A slight increase in the breadth 

 of the fins takes place just before they suddenly slope off, 

 leaving the extreme point of the tail destitute of rays, but 

 edged above and below with a scarcely perceptible cuta- 

 neous seam. The anus is placed at about one-twelfth of 

 the whole length of the fish before the middle. The skin 

 is smooth, without scales, and there is no perceptible late- 

 ral line. The specimen, after long immersion in spirits, 

 has a dusky brown colour, darker on the back, paler on the 

 belly, and without spots. 



The cojcal stomach tapers to a point, and the pylorus 

 opens obliquely through its coasts, at its upper end, so as 

 to form a valvular obstruction to the return of matter from 

 the gut. A spiral valve exists in the lower part of the gut, 

 like that which occurs in the Murce/ia;. The long and 

 slender air-bladder is thickest at its lower end near the 

 anus, and tapers upwards to a hair-like point. It is 3y 

 inches long, and sends an air-duct from its middle to the 

 oesophagus. 



Length of the fish 24 inches. To anus 1 05 inches. 

 To gill-opening 2'6 inches. 



Hab. Port Essington. 



Cuvier notices only two groups of Ophisuri in his Regne 

 Animal, one having acute cutting teeth and pectorals of 

 the ordinary size, and the other blunt teeth and extremely 

 small pectorals ; but he mentions none which have pecto- 

 rals as large as in Aiujnilla combined with small flat- 

 crowned teeth, like to those of cancrlvorus. Two other 

 Ophisuri of the same gi-oup exist in the British Museum, 

 one of which, procured from Sincapore, resembles cancri- 

 vorus closely, except that the snout is comparatively 

 shorter, and the dorsal begins a very little farther forward, 

 viz., opposite to the basal third of the pectoral, and also 

 that the pectoral itself is a little larger. The length of the 

 fish is 14 inches. The anus is only 14 inches from the tip 

 of the snout, or rather farther forward than in cancrivonts. 

 To the gill-opening 3'1 inches. The colour is a purer 

 chestnut brown, paler below the middle, and resolvable 

 there, when viewed through a lens, into minute specks. 

 The fins are dark, and the lateral line is marked by a series 

 of minute, distant pores. The differences I have pointed 

 out may perhaps be only individual variations, and without 

 access to a series of specimens it would be unsafe to name 

 this fish as a species distinct from cancrirorus. The other 

 specimen was procured at the Philippine Islands b}^ Mr. 

 Cuming, and is larger, but without any marked difference 

 in form. 



Ophisurus sinensis. Richardson. 



In the Cambridge Philosophical Institution there is an 

 Ophisunis, brought from China by the Rev. George 

 Vachell, which has so great an external resemblance to 



