GOB1US MAltTENSU. 59 



The head and operculum are naked. The gill-opening does not ascend 

 above the base of the pectoral fin; the pseudo-branchiae are large. There 

 are twenty-nine to thirty vertebra. The outline of the large pectoral fin is 

 rounded, and its longest middle rays reach back as far as the end of the 

 first dorsal. All the rays are jointed except the two or three lowest, and 

 sometimes the uppermost rays are unjointed ; but, as a rule, these rays 

 are divided. The ventral fins, with the fleshy funnel at their base, scarcely 

 attain half the length of the head. They unite laterally in front and behind, 

 forming an oval disc, which is margined by the fin-rays. The disc is free 

 behind. It is slightly in front of the base of the pectoral fins; and the 

 ventral rays, which are all jointed, except the first on each side, form a median 

 transverse fan-like fin or funnel, the middle of which has the longest rays. 



Fig. 25. ooBirs MAKTENSII (G(JNTHEK). 



There is sometimes a slightly greater interval between the rays of the 

 first and second dorsal fins in the female than in the male, but in the young 

 fish the interval is less than in the adult. The second dorsal has higher rays 

 thun the first dorsal, and it is a larger fin than the anal, which, however, 

 terminates opposite to the termination of the second dorsal fin. The caudal 

 fin is rounded, and is about one-fifth the length of the fish. It somewhat 

 resembles the pectoral fin in form. About thirteen rays in the middle of the 

 fin are jointed, and there are three or four short rays, external to these above 

 and below, which are unjointed. 



The skin is naked in the anterior part of the back as far as the first 

 dorsal, and along the throat and abdomen. Heckel and 

 Kner count thirty-six to forty scales along the lateral line. 

 The scales are limited to the sides of the fish, and become 



larger towards the tail : they are remarkably pectinate at 



. ' Fig. 26. SCALE 



the anterior edge, while the rest or the scale is marked O F GOBIUS MAR- 



with furrows, which radiate like a fan from a small centre 

 in the middle of the anterior margin (Fig. 26). Behind the second dorsal 

 six or seven scales cover the height of the fish, and at the end of the tail 

 the number is four or five. 



The colour varies in different individuals, and with the season, and may 



