1894.] PBOP. B. COIiLBTT ON A TfBW AGONOID FISH. 671 



Thus in four specimens of different sizes the proportions are the 

 following : — 



Total length 183 millim Head-length 3-66 times. 



Total length 254 millim „ 3-73 „ 



Total length 277 miUim „ 4-01 „ 



Total length 290 miUim „ 4-02 „ 



Snout very long, 3 timfes longer (or more) than the interorbital 

 space (between the bases of the supraocular spines). 



Posterior part of the head comparatively smooth, the inter- 

 orbital space rather concave ; no quadrangular pit on the occiput 

 in front of the dorsal scales. 



Eye comparatively large ; the horizontal diameter a little larger 

 than the vertical. It is contained a little more than 2 times in the 

 length of the snout, and rather more than 4 times in the length of 

 head. 



Cirri ou lower side of snout (in front of the premaxillary) and at 

 the angles of the jaws ^ Then- length equals that of the eye. 



Mouth entirely inferior ; distance from premaxillaries to tip of 

 rostral spines about equal to the length of the eye. 

 Teeth in the jaws ; vomerine or palatine teeth none. 

 Armature of the head. — Much lilte that of A. acipenserinus. 

 The rostral spines 4, two projecting horizontally forwards, two 

 (behind the first) curved backwards. A third pair on the snout 

 (much nearer the eye than the rostral spines). 



Orbital ridge with a single spine (supraocular, no preocular) ; 

 the lower ridge finely serrated. 



Occipital ridges, operculum, and preoperculum as in A. acipen- 

 serinus, but the spines more pointed and longer. 



Suborbital with a double ridge at its lower margin, the upper 

 ridge with two distinct spines behind, and a third (sometimes 

 indistinct) at equal distance from the eye and the tip of the snout. 

 Head with about 18 distinct spines altogether. 

 Armature of body. — Plates on the back and sides of the same 

 number as in A. adpenserinus, but the spines are longer and curved 

 more backwards, and strong everywhere from head to caudal. 

 Between the two dorsal keels and between the two lateral keels 

 there are no traces of another keel (as in A. valsus). 



Breast with about 10 polygonal plates, 4 of which form a series 

 on each side and 2 a median series ; bases of pectorals and ventrals 

 also surrounded with plates. All the plates have a short spine in 

 their centre. 



Dorsal plates numbering : — 



Plates. 



From occiput to first dorsal (Pair) 4 



First dorsal extending over „ 8 



Between the dorsals „ 3 



Second dorsal extending over „ 9 + 1 



From second dorsal to caudal (Single) 15 



1 All the Bpecitnens ave in a bad state of preservation and most of the barbels 

 are lost. 



