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in a fairly large cartilage; this is fused to the cartilaginous ends of the succeeding 

 interspinals. All the interspinous bones so far mentioned are unisegmented; the 

 succeeding which support the rays of the 2nd dorsal lin are bisegmented, but their 

 distal joint is cartilaginous. These interspinous bones, whose arrangement between 

 the spinous processes was described above, have the usual form but end distally 

 in cartilage; so far as I could see, the cartilaginous ends are fused into one com- 

 pressed plate in the whole group; but to this plate are articulated separate, terminal, 

 short cartilaginous pieces which are enclosed in the base of the rays. 



2. Interspinous bones of the anal fin. These are 10 in number. The 

 first lies in A.scutata with its proximal end between the hæmal spines of the 10th 

 and 11th vertebrae; the following 3 lie between the tips of the hæmal spines 11 

 and 12, the next 3 between 12 and 13, the following 2 between 13 and 14 and the 

 last close behind the tip of 14. 



The first interspinous bone is larger and broader than the others; it is con- 

 nected with the first two rays (but is certainly single, as it has but one cartilagi- 

 nous axis); the hindmost is short, broad distally and in connection with the two 

 posterior rays; otherwise each interspinous bone corresponds to one ray, but alter- 

 nate somewhat in position with these. All the interspinous bones are distally 

 cartilaginous. The cartilaginous parts are closely united, but quite clearly not 

 fused; they support a small, terminal cartilaginous piece for each ray and are thus 

 bisegmented^. 



The rays in the 2nd dorsal fin are all simple, non-articulated, as also 

 in the anal in scutata and strigata; in piinctiilata on the other hand I find that 

 some few of the rays in the anal fin are provided with a single or a few joints. 



The rays of the caudal fin are the same in all 3 species: only the 

 uppermost and the lowest small, supporting rays as also the uppermost and the 

 lowest of the long rays are unjointed, all the others are distinctly' jointed. The 

 number of rays in the unpaired fins I find in my material to be: A.scutata: D. 

 3/10-12; C. l + 4-|-5-f 1 ■ ; A. 12—13. A.strigata: D. 3/10—11; C. 1+4 + 54-1; 

 A. 11-12. A.punctulata: 3/10—11; C. 1 + 4 + 5+1; A. 12. 



The cranial skeleton. The skull in agreement with the whole form of 

 the fish is narrow and compressed. The most striking characteristics are the great 

 prolongation of the snout and the development of a part of the preopercular to 

 form a high, thin, transparent plate which covers the anterior part of the ventral 

 margin of the trunk under and in front of the gill-cover. 



Viewed from above the only bones of the skull to be seen are the supraocci- 

 pital, the frontals, nasals, mesethmoid and the vomer. The mesethnioid is almost 

 completely covered by the anterior ends of the frontals so that only a very small 

 part of it is visible; the supraoccipital projects far forwards between the two fron- 

 tals and has posteriorly an occipital process. Viewed from the side (fig. 10) we 



* 1 indicates the short supporting raj', 4 the rajs attached to the upper, S those on the lower 

 h}'pural bone. 



