DR. RICHARDSON'S DESCRIPTION OF AUSTRALIAN FISH. 183 



In. Lin. 



Height of first dorsal 13 



Height of second dorsal 12 



Height of caudal 10 



Length of caudal 2 6 



Projection of caudal beyond tip of tail 8^ 



Syngnathus ARGUS (Nob.), Ocellated Pipe-fish. — Syngnathus argus, Richardson, Zool. 

 Proceed., March 10, 1840. 



Tab. VII. Fig. 2. 

 Syngn. depressus, latus, pinnis pectoralihus pinndque dorsi prmditus, ventralibus cauda- 

 lique orbatus ; dorso maculis oculeis ornato ; in margine ventris maculis albis und 

 serie dispositis. 

 In the ' R^gne Animal ' Cuvier groups the pipe-fish by the number of fins which they 

 possess, but he mentions none which are like this species destitute of caudal and ven- 

 trals, and at the same time furnished with pectorals and a dorsal. In the depressed 

 form of the body the Syngnathus argus resembles the 8. perlatus of Beechey's Zoolo- 

 gical Appendix, but that species has a caudal fin. 



Form. — Four-sided, the body depressed, the belly convex, between three and four 

 times wider than the narrow back, the sides consequently sloping to unite the two. 

 The body gradually widens from the pectorals to the dorsal (where the width is twice 

 the height), and then as gradually contracts again until it passes that fin some way, 

 the form changing insensibly into that of a tapering equilateral, rectangular tail, which 

 ends in a point. The whole length contains six and a half lengths of the head, and the 

 anus is rather before the middle of that length. Other proportions may be learnt from 

 the table of dimensions. 



The hair-brown back and sides are studded in a very beautiful manner with oval black 

 spots having white borders, about twenty on each segment, and at the acute union of the 

 side with the belly there is one oblong milk-white spot on each segment. The belly is 

 pale and unspotted. 



There are sixty-eight segments in all, including the minute tip of the tail, which 

 under the microscope appears to be slightly notched. Twenty segments or plates may 

 be counted on the belly before the anus, and there are forty-eight behind including the 

 one which contains the aperture. There are eleven anterior to the dorsal, which ex- 

 tends over eighteen more and a part of the nineteenth, behind which there are thirty- 

 eight : so that the dorsal extends eight segments beyond the anus. 

 Rays. — D. 48 ; P. 15 ; the first one short. 



The pectorals are small and have a rounded outline. The two or three first rays of 

 the dorsal are a little shorter than the succeeding ones, which continue nearly of one 

 length to the posterior quarter of the fin, when they gradually but shghtly decrease in 



height. 



2b 2 



