156 Memoirs of the Indian Museum. [Voi,. II, 



The lateral line is single, uninterrupted, very broad, and conspicuous ; it runs 

 from the upper angle of the gill-opening to the base of the caudal, curved slightly 

 downwards, and contains a row of about 41 distinct pores. 



Two separate dorsal fins: the first begins slightly posterior to the vertical through 

 the base of the pectoral, and contains 8 slender spines ; the second begins a couple of 

 millimetres behind the first, is much the longer, and contains 27 rays. The anal is 

 equal, opposite and similar to the second dorsal. Caudal symmetrically forked. Pector- 

 als long (about half the length of the head) and slender, in position nearer the ventral 

 than the dorsal line ; all rays branched. Ventrals (I, 5) short (not so long as snout), 

 inserted below the pectorals, but connected only by ligament with the clavicular arch. 



Vent about 8 mm. in front of where the anal fin begins. No anal papilla ; small 

 urogenital papilla behind the vent. 



The jaws are distensible, with four series of setiform teeth similar in both jaws ; 

 those of the inner rows longest ; all movable and turned inwards. No vomerine teeth ; 

 a single row of small teeth — depressible backwards — on each palatine. Tongue free. 

 Gill-openings very wide, with membranes joined only quite anteriorly. Seven bran- 

 chiostegals. Gills four ; last gill-cleft a foramen merely. Branchial arches weak and 

 gill-rakers represented by small fixed and fairly numerous teeth similar to those of the 

 mouth. Pseudobranchiae are present. 



An air-bladder is present, but without an open duct. The pyloric caeca were 

 densely matted together and entangled with parasitic worms ; there were about nine 

 caeca. Beside these the hepatic duct opened into the gut. Vertebrae 39 (15 abdomi- 

 nal and 24 caudal). Abdomen extends well behind the vent into the tail. The 

 stomach is elongate, caecal in shape, and empty ; its inner surface presented large 

 coarse, longitudinal rugae. Liver small. 



The colour in life was violet-black. A single specimen about 9^ inches long ; was 

 caught in the trawl at Station 315, Bay of Bengal, near the Andamans, 705 fathoms." 

 (MacGilchrist.) Registered No. ^^f-^. 



I think that the word ' ' minute ' ' which is applied to the spiny scales should be 

 omitted These structures are the most remarkable peculiarity of the genus. They 

 are arranged in four irregrdar rows parallel to the lateral line in the posterior part of 

 the body. Each spine arises from the centre of a circular disc which may measure 

 over a millimetre in diameter ; the spines are slender, transparent and upright, and 

 curve slightly with the concavity directed backwards. Some of them project from the 

 disc by as much as a millimetre. 



The parasitic worms referred to have been since identified by Prof, von Linstow 

 as immature examples of a species of Ascaris. 



Family TETRAGONURID^,. 



Genus Mui^ichthys, no v. 



Resembles Tetragonurus, the only other genus of the family, in the form of the 

 body and general arrangement of the fins and in possessing oesophageal sacs lined by 



