COTTUS GOBIO. 51 



pectinate, while the pharyugeal bones possess villiforra teeth. The gill-arches, 

 with the exception of the first, possess rake-like teeth. 



The first dorsal fin begins over the base of the pectoral, and possesses in 

 most individuals eight undivided rays, of which the middle and longest rays 

 are one-third the height of the body. A narrow membrane unites the first 

 dorsal with the second dorsal, the first ray of which is very short, while 

 the fourth to the sixth rays are longer than any in the first dorsal. Its 

 rays are all undivided. The anal fin begins behind the second dorsal, and 

 does not reach so far back. One specimen from the Tyrol has only nine 

 rays in the anal fin. Its longest rays equal those of the dorsal fins. All 

 are simple spines with the exception of the last, which is usually 

 divided to the base. The ventral fin commences a little behind the pectoral, 

 its spinous ray is joined to the first of the four simple soft rays. They 

 never reach back beyond the last ray of the first dorsal. In Scandinavia 

 the rays of this fin are branched. The pectoral fins are very much de- 

 veloped ; their length is nearly one-fourth of the length of the fish, and they 

 reach back to the beginning of the second dorsal fin. Their aspect is that 

 of a broad, rounded, expanded fan. Young individuals have the rays un- 

 jointed, but with age jointing begins with the first and extends gradually 

 to five or six rays, but the succeeding rays always remain simple. The 

 rounded caudal fin generally measures one-sixth of the total length ; its 

 eight middle rays are all jointed. The anal aperture lies in the fore part 

 of the body, and behind it is the long genital papilla, which is of different 

 form in the two sexes. 



The head and body are without scales. The lateral line is in the upper 

 third of the body in its anterior part, but afterwards descends to the 

 middle, and its mucus-canals open in from twenty-six to twenty-eight simple 

 pores. The pores of the cephalic canal extend along the lower jaw. 



The colour varies, but always has a ground tint of grey ; the back 

 is often some shade of brown, spotted with dark brown, or flecked or clouded 

 with brown colour, which sometimes forms transverse bands. The belly is 

 whitish-grey, occasionally streaked with brown. The dorsal, pectoral, and 

 caudal fins are covered with brown stripes, which usually extend along the 

 rays, though the skin is sometimes banded. 



The anal fin is not banded with colour, and the ventral fins are mostly 

 unstreaked, or possess only a few scattered spots. 



The first dorsal fin is reddish. The iris is red. 



The stomach is a broad, round sac with three or four rather wide pyloric 

 appendages. The abdominal walls are covered internally with a black pig- 

 ment. There is no air-bladder. The milt of the male is double, and, like 



