two limbs are in close contact, and cannot be separated. 

 When the mouth is closed, these teeth are pressed against 

 the equally prominent nasal ones, the posterior teeth of 

 the two jaws being kept thereby some distance apart. 



Eye small, considerably before the luiddle of the gape. 

 Posterior nasal orifice having an elevated border, and 

 ])laced a little before the eye. Anterior one shortly tubu- 

 lar. Dorsal fold of loose skin extending forward to the 

 nostrils, too thick to allow the rays to be either seen or 

 felt. Body compressed, the compression augmenting to- 

 wards the tip of the tail, which is not acute though it 

 tapers. Anus in the posterior third of the length. 



Ground colour brown, with seventy-four white rings, 

 some of which are not complete, and some unite before 

 they reach the ventral surface, but the greater part are 

 regular, and are all nearly of the same width. 



This description is taken from Shaw's specimen, which 

 was presented by the College of Surgeons to the British 

 Museum. The backward position of its anus and other 

 characters seem to point it out as a distinct generic form 

 from Murcena. 



Length 30 inches. To anus 21 inches. To gill-opening 

 ■2 6 inches. 



Hab. Sumatra (Shaw). New Britain (Commerson). 



ICHTHYOPHIS TIGRINUS. LeSSOn. 

 Ichthyophis tigrinus, Lesson, Voy. de la Coquille, pi. 12. 



All the teeth slenderly subulate, rather tall and thinly 

 set. Nasal ones uniserial, about twelve on the margin. 

 Two rows of three each on the disk. Vomerine teeth six 

 or seven, uniserial, with two abreast at the commencement 

 of the series. Palatine teeth biserial ; the outer series of 

 twelve more reflex teeth ; the inner series of six or seven 

 taller ones. On the anterior third of the mandible the 

 teeth are biserial, the inner row being composed on each 

 limb of six or seven taller ones. Lateral mandibular teeth 

 like the outer row of palatines. 



Eye small. Anterior nostrils tubular. Posterior ones 

 injured. Gill-opening nearer to the dorsal than to the 

 ventral surface. Body nearly cylindrical, destitute of a 

 loose dorsal fold. Tail a little compressed at the tip, 

 which tapers, but is blunlish. No vestige of a fin exte- 

 riorly. 



Length 29 inches. To anus 195 inches. To gill-open- 

 ing 1-85 inch. 



The great length of this fish in proportion to its diame- 

 ter, its cylindrical form, and the want of fins, give it a 

 character distinct from the MuiceiKe, and from the Gymiw- 

 murieniB of Lacepede, which are compressed. 



Hab. " Oualan." 



Nettastoma vittata. Richardson. 



h-hthynphis viltaius, Ricbardsoii, Iclith. of Voy. of Sulphur, p. 114, 

 pl. 53, f. 7 !). 



Since I described this species, in the work above quoted. 



from a dried skin, said to have been brought from China, 

 1 have examined a specimen in spirits in the British Mu- 

 seum, which is labelled as having been brought from the 

 West Indies, and purchased of a dealer. I have also had 

 an opportunity of inspecting an example of the Ichthyo- 

 phis tic/riniis of Lesson, preserved in the same collection, 

 and find that it differs totally in its dentition from the 

 present species, so that in any dismemberment of the genus 

 Murcena they must be placed in widely different groups. 

 I have now referred it to Rafinesque's genus Netiasioi/ia 

 (Duck-mouth), on account of the similarity of its dentition 

 to that of N. soya, though I have not had an opportunity 

 of seeing the latter species, which differs from vittata in 

 having conspicuous fins, and may prove on examination 

 to be a distinct form, in which case the appellation of 

 Chaiuw-mura'na vittata may be given to this one, its ver}' 

 large mouth distinguishing it obviously from the Minuena. 



It has four large double-leaved gills enclosed in a sack 

 on each side, and communicating with the pharynx by five 

 round openings. There is no half-gill adherent to the side 

 of the sack. The heart is situated rather behind the gill- 

 openings, and at a considerable distance from the gills, 

 and is tied to the pericardium by many tendinous threads. 

 There is no tongue, but the under margin of the gullet 

 forms a projecting soft fold, which falls back over the oeso- 

 phagus like a valve. Pharyngeals presenting two linear 

 dental surfaces above and below, widely separated from 

 each other, and set with two rows of acute reflex teeth. 



All the teeth on the jaws are slenderly subulate, and are 

 disposed in even card-like plates. On the palatines they 

 are about four rows wide, just behind the eyes, but thin off 

 to three rows towards the extremities of these bones. On 

 the lower jaw the dental surface is broadest near the sym- 

 physis, where there are three rows of teeth, but there are 

 only two rows more posteriorly, which end in a point at 

 the corner of the mouth. The nasal and vomerine teeth 

 are not separated, or perhaps the latter do not exist, in 

 which case the nasal dental plate is broadly oval, and com- 

 posed anteriorly of about six rows in the width, but poste- 

 riorly contracts to two rows, which meet in a point a little 

 behind the eye. The capacious roof of the mouth is lined 

 with smooth skin. The corners of the mouth extend as 

 far behind the occiput as that is distant from the tip of the 

 snout. The small eye is situated over the fore part of the 

 gape. The anterior nostrils are tubulai-, and the posterior 

 ones have raised borders, and are placed above and just 

 before the eyes. 



The head is depressed, the nose acute, and the mandible 

 longer than the snout: its limbs are capable of sepa- 

 rating widely, and, owing to their length, of being greatly 

 depressed, so as to expand the mouth enormously. The 

 gill-openings are rather below mid-height, and far behind 

 the skull. The body is nearly cylindrical, without any 

 appearance of the loose dorsal fold which contains the fin- 

 rays in the Murwnic ; but behind the anus the tail is some- 

 what compressed, becoming thinner towards the tip. Rays 

 actually exist near the end of the tail, but they can be 

 seen only by dissection, and I could not ascertain how far 

 forward they extend without injuring the specimen. The 

 anus is in the posterior third of the fish. The skin is 

 loosely attached to the muscular fascia. 



