210 PROCEEDINGS OF THE ACADEMY OF 



Ventral fins bifid and articulated, moderately developed and nearly or quite 

 as long as the head. 



Pyloric appendages none. 



Type. Ophidium barbatum Linn. 



Genus LEPTOPHIDIUM Gill. 



Body much elongated, moderately compressed, and with the back and abdo- 

 minal regions arched, more compressed and slowly decreasing in height back- 

 wards to an abruptly-rounded point. 



Anus towards the end of the first third of the length. 



Scales regularly imbricated in quincunx, oval, with the nucleus in front of 

 the centre, and with strias radiating backwards. 



Lateral line concurrent with and near the back for about half the length, 

 obsolescent behind. 



Head with imbricated scales extending to forehead, opercula and cheeks, 

 moderately compressed, oblong-ovate in profile, with the snout high, project- 

 ing forwards, and obtusely rounded, armed above with a short, nearly con- 

 cealed spine, directed forwards and somewhat downwards. Cheeks somewhat 

 inflated. Eyes large, subcircular, with comparatively small pupils. Nostrils 

 double; the anterior aperture a short tube directed forwards and next to the 

 groove separating the preorbital from the nostril region ; the posterior a longi- 

 tudinal fissure in front of the eyes below the preorbital groove, Opercula un- 

 armed. 



Mouth broader, with the cleft little oblique and moderate ; the supermaxillar 

 bones are slender, terminate under the hinder part of the eye, and are almost 

 wholly retractile under the suborbitals. 



Teeth of the jaws villiform, immersed in a mucous membrane, separated by 

 an interval from the longer ones in the outer row, which are pointed and 

 moveable. 



Vomer not prominent, armed, as well as the palatine bones, with teeth. 



Branchial aperture ample, arched above by the membrane, which is at- 

 tached in front of the axil of the pectoral fin. 



Branchiostegal rays seven, the internal two small. 



Dorsal fin commencing less than a head's distance from the nape, rather low 

 and with its rays simply articulated, blending behind, like the anal, with the 

 caudal fin, whose rays are lon-er than those of the dorsal and anal, and whose 

 margin is produced. 



Pectoral fins small or moderate, obliquely rounded behind. 



Ventral fins bifid and articulated, and much abbreviated. 



This genus is exceedingly distinct from Ophidium, having very few characters 

 iu common, except such as would be found in the genera of the same subfamily. 

 Its form at oace distinguishes it, \ii comparatively low and moderately com- 

 pressed body and the smaller head contrasting strongly with the much com- 

 pressed body and head of the true Ophidia ; the imbricated scales and pe- 

 culiar dentition observed on closer examination corroborate the generic dis- 

 tinction indicated by the difference of form. 



It is probable that the Ophidium brevibarbe, briefly indicated by Cuvier and 

 Kaup, belongs to this genus ; by Cuvier, it was simply alluded to in afoot-note 

 of the Regne Animal, while by Kaup a short diagnosis was given in the " Cat- 

 alogue of the Apodal Fish." As the notice of the species by Kaup, like most of 

 the diagnoses by that gentleman, is only sufficient to distinguish it from 

 species known to him, no clear idea can be obtained regarding its affimities. 

 But, as it is said to have " on the point of the snout a short decurved spine," 

 "scaly occiput and gill-plate, and long, tapering pointed caudal fin," while 

 "the remaining species are destitute of the rostral spine, and have fewer or no 

 s'cales on the occiput and gill-covers, they are also shorter," it is likely that 

 a species somewhat related to the Leptophidium was iu view. Before the 



[Aug. 



