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covered by some smnll, tliin bony plates (fig. 10 and 13 a' a"), which form a con- 

 tinuation of the antorbital. These occur in somewhat varying number; in A. scutata 

 I have as a rule found 2 on each side, most frequently (a' a" as the figs, show) 

 the first is quite short, the posterior longer, rarely the reverse; in A. strigata I find 

 as a rule 4 on each side; in a specimen of A. piinctulala 2 on the left, 3 on Ihe 

 right side, in another 3 on 

 the right, 4 on the left side. 

 In all the posterior end of 

 the hindmost lies under or a 

 little behind the front end 

 (with the lateral line pore) of 

 the nasal. As these small 

 bones appear in close contact 

 and in line with the front 

 end of the antorbital, with 

 the same function as this, and 

 as they also seem somewhat 

 inconstant in number, in two 



of the species often ditTerent on the two sides, we may well consider them as dis- 

 connected parts of this bone. They seem to me to have special interest as they 

 give us the key to understand the relatively much larger bones, which occur in 

 the true Lophobrancliii in quite a similar position. 



hy 



Fig. 13. 

 Anipliisilc sciildlii. Lel'l lateral aspect, seen from nutsiilc, ol' the anterior 

 end of niantlibuliiry suspensorium and parts of the mouth, freed from 

 the skull, i: inlermaxilla: inx: maxilla; d: dentary; ar: articular; an: 

 angular; pa: palatine; ekt, ept: ecto- and cnloptcrygoid. Other letters 

 as in fig. 10. 



Fig. 14. 



Amphisile scutata, Mandibulary suspensorium and opercular bones with Ihe 4 branchioslegals, 



right side, seen from within. Ity: hyonumdibuhir; sy: symplectic; qii: quadrate; eki, cpt, ntt : 



ecto-, ento- and mctapterygoid; pa: palatine; a", see figs. 10, 13; io: interoperculum ; pro: preo- 



perenlum : o; operculum; s: subopercnluni ; /■; t)ranchiostegals. 



The true mouth-parts (fig. 13) are small. The intermaxilla (i) has a distinct, 

 though weak, ascending branch; the maxilla (mx) is relatively of fair size and as 

 elsewhere in the bony fishes supported above by a process from the palatine (pa). 

 The lower jaw is composed of the usual 3 parts on each side: the articular (a) 

 and dental (d) which together form a high ascending process for the attachment 

 of the tendon of the M. adductor mandibulœ, and a small angular (an), which is 

 connected with the interoperculum as is usual by a ligament. At the front end of 

 the dental there is a blunt or sometimes a quite pointed hook directed downwards. 



