FAMILY, I— SILURID^. 483 



the inner ones. Fins— dorsal spine serrated on both edges, and equal to 2/5 of the length of the head, pectoral 

 spine similar and equal to 1/3 of the length of the head. Golov/rs — brown, the vertical fins edged with black. 



Plotosus limbatus, C. V. xv, p. 422 ; Giinther, Catal. v, p. 25, is said to differ in its 2 D + C + A:=224 

 rays : its head and also its nasal barbels being a little shorter. 



Bleeker observes that the Malays at Batavia believe that the flesh of this fish has emmenagogue 

 properties. 



EaUtat. — Estuaries of India and Burma to the Malay Archipelago. It attains 3 feet and upwards 

 in length. 



2. Plotosus Arab, Plate CXII, fig. 4. 



Silwrus Arab, Porsk. Desc. Anim. xvi, No. 36. 



Platysiacus anguillaris, Bloch. viii, p. 61, t. 373, f. 1 ; Bl. Schn. p. 373, t. 74 ; Shaw, Zool. v, p. 30, 

 t. 99 ; Eussell, Pish. Vizag.' ii, p. 51 and Ingelee, f. 166. 



Plotosus cuiguillaris, Lac6p. v, p. 130, pi. 3, f. 2 ; Cuv. Reg. Anim. ; Riippell, N. W. Pische, p. 76 ; 

 Cantor, Mai. Pish. p. 264; Peters, in Wiegm. Arch, xxi, p. 267; Bleeker, Silur. p. 314; Giinther, Catal. v, 

 p. 24. 



Plotosus ilewpor, Less. Voy. Coq. Zool. ii, pi. 31, f. 3. 



Plotosus margmatus, Bennett, Life of Sir S. Raffles, p. 691. 



Plotosus Imeatus, Cuv. and Val. xv, p. 412 ; Rich. loh. China, p. 286 ; Schleg. Pauna Japon. Poiss. 

 p. 228, pi. 104, f. 3 ; Bleeker, Silur. Batav. pp. 4, 17, 57. 



Plotosus castaneus, Cuv. and Val. xv, p. 421. 



Plotosus vittatus, Swainson, Pishes, ii, p. 307. 



Clarias angmllaris, Swainson, Pishes, ii, p. 307. 



Plotosus castcmeoides, Bleeker, Nat. Tyds. Ned. Ind. ii, p. 490. 



Plotosus Arab, Bleeker, Atl. Ich. Silur. p. 98, t. 95, f . 2 ; Kner. Novara Pische, p. 300 ; Day, Fishes of 

 Malabar, p. 195 ; Klunz. Verb. z. b. Ges. Wien, 1871, p. 588. 



Moorghee, Mai. 



B. xi, D. ^T, 2 D + C + A 169-190, P. 1/11, V. 12, Yert. 12/35. 



Length of head 5 to 6^, heighfof body 7 to 8 in the total length. Pliies—diaxo.eter 6 to 6^ of, and situ- 

 ated in the middle of the length of head, the width of the interorbital space equals 1/3 of the length of the head. 

 Greatest width of the head equals its length behind the angle of the mouth. Upper jaw slightly the longer, 

 the width of the gape of the mouth equalling 2/5 of the length of the head. Barbels — the nasal reach the hind 

 edge of the eyes, the maxillary 1/2 to 2/3 as long as the head, the mandibular ones are shorter. Fins — dorsal 

 spine rather strong, 1/3 as long as the head and serrated on both sides. Colours — chestnut-brown, with two 

 bluish-white longitudinal bands, the superior proceeding from above the eye along the base of the dorsal 

 fin, the inferior from the maxilla along the middle of the side of the body. Bleeker observes that these bands 

 entirely disappear in adults. Vertical fins with black edgfes. 



Woiinds from the pectoral spines of this fish are much dreaded by the natives of India as occasioning 

 phlegmonous inflam.mation or even tetanus. 



Eabitat. — From the Red Sea and East coast of Africa through the seas of India to Japan and Polynesia. 



B. Avr-vessel more or less enclosed in bone.* i 



Genus, 17 — ClAeias, Gronovius. 



Maoropteronotus, Lacepede ; Gossyphus and Phagorus, McClelland. 



Branchibstegals seven to wine. Oill-openings wide, the membranes not being eonjluent with the skin of the 

 isthmus, and separated by a deep notch. A dendritic accessory branchial apparatus attached to the convex side of the 

 second, third, and fourth branchial arches is received into a recess above and behind the usual gill-cavity. Head 

 depressed, gape of mouth of moderate extent, anterior and transverse. Eyes small, with a free circular margm. 

 Barbels eight, 'Teeth villiform in the jaws and in a band across the vomer. Dorsal fin long and spineless, extending 

 from the neck to the caudal, with which it may be continuous : no adipose fin. Ventral with six rays. Pectoral with 

 a spine. Air-vessel small, troMsverse, lobed, and enclosed in bone. 



Mr. Kitchen-Parker, P.R.S. (on the shoulder girdle, Ray Society, 1868, p. 29) observes of the air-vessel 

 and its surroundings in Ola/rias. "The remarkable trumpet-shaped cavities belong to the A.tlas and Axis 

 vertebrae, and they are strongly attached to the post-temporals and clavicles at their point of junction : they 

 lodge the lateral cornua of the three lobed air-bladder. These cavities are very imperfect below : but this 

 deficiency is largely supplemented by a transverse splint on each side, attached, below to the anterior edge of 

 the great cylinder of the atlas. There is a smaller splint in each cavity, and two smaller sphnts eke 



* This provisional subdivision of the Siluroids is adopted merely .for the sake of convenience. A considerable number of 

 dissections will be necessary before the grouping of this family can be satisfactorily arranged. In some of those forms m which the 

 air-vessel is partially enclosed in bone such is effected by the auditory ossicles, in others by being enclosed in osseous capsules formed 

 from a vertebra, or ossified to the vertebrse. Placing the amphibious Clarias in the same sub-familv with Plotosus und Chaca, and 

 putting the amphibious Saccobramchus in another sub-family along with the non-amphibious Siki/rus, Wallago, andifutropitchthys does 

 not seem natural. I have here followed Bleeker in placing the amphibious Clarias next to the equally amphibious SaacobrancJms. 



3 Q 2 



