CARASSIUS BUCEPHALUS. 113 



blunter head, large projecting eyes, and smooth scales ; and it differs from C. 

 humilis in height of body, number of horizontal rows of scales, and shortness 

 of the pectoral and caudal fins. 



The profile of the head is flatter than in the Crucian Carp. The body is 

 much thicker, and less elevated. Over the pectoral fins the thickness is equal 

 to nearly half the height in front of the dorsal, which is about a third of the 

 entire length. 



The head is one-fourth of the entire length ; it is thicker than the body, 

 and noticeable for its broad forehead. The large wide projecting eyes are 

 nearly one-third the length of the head. Their posterior border is behind the 

 middle of the head, and the width of the inter-orbital space is equal to one- 

 half the length of the head. 



The mucus-canals are well developed ; their pores are conspicuous to the 

 naked eye, and situate in small papilla?, which, as in most Cyprinoids, extend 

 above and below the eye, along the lower jaw and the margin of the pre- 

 operculum. In form and position the mouth resembles that of the Crucian 

 Carp. The fins are similar to those of C. vulgaris. The dorsal fin extends 

 between the middle of the body and thefirst ray of the anal fin. 



The scales are not quite so large as in the Crucian Carp. The lateral line 

 is marked by small pores, but the scales are not perforate behind the ventral 

 fin, so that there are only about twelve to sixteen scales, with mucus pores. 

 The scales are smooth, and have the free margin marked with from two to 

 four diverging rays. The colour is only known from specimens preserved in 

 spirit, when the upper part of the sides and back are black, on a ground which 

 has a silvery lustre. The under side is a dull yellow. There is a large annular 

 spot on the tail adjacent to the caudal fin. 



Specimens are about five inches long. 



GENUS: BarbUS (CuviER). 



The Barbels form a large genus, widely distributed, and presenting consider- 

 able diversity of character. Dr. Giinther remarks that a further division of the 

 163 species which he enumerates must appear highly desirable; yet adds that 

 nothing would be more contrary to the idea of natural genera, since the transition 

 is perfect from one extreme species to the other. He believes that the 

 size of the scales, the development of the third dorsal ray, and the form of the 

 snout are useless as generic characters, because complete series of intermediate 

 forms are met with. The lips, too, present in the same species variations which 



