FAMILY, I— PERCID^E. 



spine is longer but not quite so strong as the second, its length equals that of the fourth of the dorsal fin : caudal 

 deeply forked, its upper lobe slightly the longer. Scales — two rows on the suborbital ring of bones, the lower of 

 which is much the deeper. Lateral-line — interrupted after about from the eighth to the twelfth scale, in some 

 specimens it ceases entirely. Pseudobrancliice — well developed. Colours — silvery with a bright longitudinal 

 lateral band, some brown spots on the upper third of the body in its front half : blackish between its second and 

 third dorsal spines, also a black edge to the caudal. 



In examining a large number of these fish the first thing that strikes one's attention is the variation in the 

 length of the second and third dorsal spines, sometimes one, sometimes the other being the longer. Not only 

 do they vary between themselves, but likewise as regards their comparative length to that of the remainder of 

 the body. The undermentioned specimens are taken at random from upwards of fifty in my collection. 



inches. inch. inch. 



No. 1. total length 1^, exclusive of tail 1 : height of dorsal spine 3/10 : or 3j in length of body, excluding the 



caudal fin. 



2. 



11 ) 



2 



55 MO 



3." 





2-L 



1-9- 



55 i 10 



33 > 



^10 11 



4. 





9_§_ 



1- S 



55 ^10 



33 3 



1 -10 " 



5. 



33 J 



9^_ 



' "10 11 



1-S- 



55 i 10 



6. 



JJ J 



, 2 A „ 



55 ^lO 



7. 



3? 3 



9_s_ 



5 -10 55 



55 ^10 



8. 





9_s_ 



2- 2 - 



55 ^10 



33 3 



5 -10 55 



9. 





0_8_ 



2-&- 



3? J 



5 -io •>•> 



55 J 10 



0. 



33 J 



, 3 



2-3- 



55 '10 



4/10 



33 



3f 



4/10 



33 



1/4 



4/10 





4| 



4/10 



33 



4| 



4/10 



33 



4 



5/10 



33 



44- 



5/10 



33 



4* 



5/10 



33 



4f 



4/10 



33 



H 



The foregoing distinctly shows how the comparative length of the dorsal spines to that of the remainder 

 of the body decreases with age, and renders it probable that Ambassis Buruensis, Bleeker (Boeroe, p. 396), is very 

 closely allied to this species. 



Habitat — East coast of Africa, seas of India to the Malay Archipelago and China: it attains at least 

 4 inches in length. Although generally captured in the sea or saline backwaters, I obtained a specimen from 

 the fresh water in the Cochin State several miles inland. 



10 Ambassis urotssnia, Plate XV, fig. 8. 



Bleeker, Amb. and Ceram, p. 257 ; Griinther, Catal. i, p. 224. 



? Ambassis denticulata, Klunz. Verh. z. b. Ges. in Wien, 1870, p. 719. 



B. vi, D. 7^.^05 P- 13, V. 1/5, A. T .Vo, C. 18, L. 1. 27-28, L. tr. 3-4/10. 



Length of head 1/4, of caudal 1/4, height of body 4/13 of the total length. Eyes — diameter 2/5 of length of 

 head, 1/2 a diameter from end of snout, and 3/4 apart. Lower jaw the longer : cleft of mouth very oblique. The 

 maxilla reaches to below the front edge of the orbit. Preorbital with seven sharp teeth along its inferior edge : a 

 spine at the posterior-superior angle of the orbit. Vertical limb of preopercle entire except two serrations just above 

 its angle : its horizontal double edge serrated, the lower the most coarsely so : sub- and inter-opercles entire. 

 Teeth — villiform in jaws, vomer, and palate : a small central band at the root of the tongue. Fins — second spine 

 of the dorsal longest and equal to one quarter or two-ninths of the total length, and rather above half the height 

 of the body below it : ventral reaches two-thirds of the way to the anal fin : third anal spine usually slightly the 

 longest but not equalUng the longest of the dorsal. Scales — a single row along the suborbital ring of bones. 

 Lateral-line — curves downwards under the middle of the soft dorsal, but in an interrupted or semi-interrupted 

 manner. Colours — Silvery with a burnished lateral band : the interspinous membrane between the second and 

 third dorsal spines black : a dark longitudinal band along either lobe of the caudal. 



Dr. Gunther observes, P.Z.S. 1871, p. 655, that Ambassis miops, Giinther, differs from A. urotcriiia. 

 Bleeker, by the smaller size of the eye, and by the lateral-line being continuous. The diameter of the eye in 

 A. wrotceniab is equal to the length of the postorbital portion of the head. In A. miops the lateral-line forms a 

 distinct and continuous curve from opposite the end of the dorsal fins, whilst there are two rows of scales along 

 the suborbitals. 



Habitat. — Seychelles, Andamans, and the Malay Archipelago. It closely resembles the A. gymnocephalus, 

 but its lateral-line is entire : it has only one row of scales along the suborbitals and the comparative height of its 

 body differs. It appears to be common at the Andamans.* 



* Bogota infuscata. 



Blyth, J.A.S. of Bengal, 1860, p. 139 ; Dav, Proc. Zool. Soc. 1869, p. 515. 



D. 10/ T V, V. 1/5, A. 3/8, C. 17. 



Preopercle strongly serrated with large teeth at its angle. A spine directed backwards, apparently on the subopercle. A long 

 spine on the opercle. Preorbital entire. Lower jaw the longer. Teeth — in jaws yilliform. Fins — second anal spine the longest. 

 Scales — none now visible. Colowrs — brownish-black, except! the fins, which are of a dirty yellowish white. 



The specimen is half an inch long and in a very bad condition. The occiput is broken across : in fact it is now too damaged to 

 admit of a complete description. One thing is evident, that it does not belong to the genus Ambassis, it may be the fry of a species of 

 Priacanihus. For these reasons I refer to it in a note. 



Blyth described it thus : "a minute species (if adult) T \ in. long by 1-J- in. depth, rmwas the fins : with the tail much less forked 



