BY W. MACLEAY, F.L.S. 203 



Family I. SILUKIDiE. 



Skin naked or with osseous scutes, but without scales. Barbels 

 always present ; maxillary bone rudimentary, almost always 

 forming the base of a maxillary barbel. Margin of the upper 

 jaw formed by the intermaxillaries only. Suboperculum absent. 

 Air-bladder generally present, communicating with the organ of 

 hearing by means of the auditory ossicles. Adipose fin absent 

 or present. 



Genus Plotosus, Lacep. 



A short dorsal fin in front, with a pungent spine ; a second 

 long dorsal is united with the caudal and anal into one fin, which 

 is pointed behind. Teeth in the upper jaw conical, on the vomer 

 molar-like, in the lower jaw mixed. Barbels eight: one 

 immediately before the posterior nostril, which is distant from 

 the anterior, the latter being quite in front of the snout. Cleft 

 of mouth transverse. Eyes small. The gill membranes are 

 separate from each other, not attached to the isthmus." Branchial 

 arches without particular cartilaginous posterior process and 

 without posterior membrane. Ventral fins many-rayed. Head 

 depressed. 



Coasts of Indian and Polynesian Seas. 



802. Plotosus anguillabis, Lacep. 



Gunth., Cat. Pishes, V., p. 24.— Cant. Pishes Mai., p. 264. 



Plotosus arab, Bleek., Atl. Ichth. Silur., p. 98, tab. 95, fig. 2. 



B. 12. Pirst D. 1/4-5. Second D. + C.+A. 169-189. P. 1/11, 

 V. 12. Vert. 12/35. 



The length of the head is about one-fifth of the total length 

 (without the caudal fin), the height of the body one-seventh or 

 one-eighth. Barbels not very long : those of the nostril extend 

 to the eye, and those of the maxillary are about half as long as 

 the head. Brown or black, generally with two white longitudinal 



