50 TELEOSTEI : EVENTOGXATIII. — XII. 



epidermis. Tiie fins aiid otlier ])arts are often eliarjiod with pig- 

 ment, the usual eulor being red, but sometimes satiu-white, yellow- 

 isii. or blaek. 



Note. — Young Cyprinida are usually more slender than adults of the 

 »anie spocics, ami the eye is always imich larfjer; they also frequently show 

 a lilack lateral stripe anil caudal spot, wliic h the adults may not possess. In 

 the followiu;^ descri|)tions, the rudimentary rays of dorsal and anal are not 

 counted. The tins and scales are often, especially in specimens liviuf; in snuill 

 jrooks, covered with rouiul black specks, parasitic plants. These should not 

 be mistaken for true color-markinps. 



No pro^jress can be made in the study of these fish without careful attention 

 to the teeth, as the penera are largely based on dental characters. The 

 pharyngeal bones in the smaller species can be removed by inserting a j)in (or, 

 ' itter, a small hook) through the gill opening, uiuler the shoulder girdle, 

 riie teeth should be carefully cleaiU'd with a tooth-brush, or, better, a jet of 

 water, and when dry may be examined by any small lens. In most cases a 

 principal row of four or tive larger teeth will be found, in front of which is 

 a set of one or two smaller ones. The two sides are usually, but not always, 

 symmetrical. Thus, "teeth 2, 4-5, 1," indicate two rows of teeth on each 

 side, on the one side four in the principal row and two in the lesser, on the 

 other side five in the main row and one in the other. " Teeth 4-4 " indi- 

 cates a single row of four on each pharyngeal bone, and so on. 



In the Leucigcine genera, these teeth, or the principal ones, are " rapta- 

 *orial," that is, hooked inward at the tips. A t/rintling or masticatory »UT{aoe 

 is an excavated sjiace or groove, usually at the base of the hook. Sometimes 

 the grinding surface is very narrow and confined to one or two teeth. Some- 

 times a bevelled or flattened edge looks so nnich like a grinding surface as to 

 mislead a superficial observer. In some cases, the edge of the tooth is crenatc 

 or serrate. 



Besides the native species here mentioned, representatives of two other 

 genera have been introduced fmm Europe, and have become inhabitants of 

 some eastern streanis. These are Ci/jnintis I>iiui.i-us, and Cnrnssim Nilsson. 

 The first is distinguished by the very long dorsal, which, like the anal, is pre- 

 ceded by a strong spine, serrated behind. About the mouth are four long 

 barbels, and the teeth are molar, 1, 3 -3, 1. This genus is represented by 

 the Carp (Cyprinus carpio L.). The carp is normally covered with large 

 scales. In domestication, however, variations have arisen, prominent ones 

 being the " I.«ather Carp," naked, and the " Mirror Carp," with a few sericB 

 of very large scales. 



Cnriissius Nilsson differs from Cyprinus, chiefly in the absence of barbels, 

 and in having the teeth compressed, 4— t. The (iold-fish (('(imssiiis nuratiii 

 L.) is originally olivaceous, but only the orange-red variety is valued for 

 aquaria. Both Carassiiu and Cyprinus are native in China. 



a. Air-bladder surrounded by many convolutions of the very long alimentary 

 canal, which is G to !) times the length of the body. (Cnm/wsinmitup.) 

 b. Teeth 4-4, or 1, 4-4, 0, with obli(|UP grinding surface and slight hook; 

 {KTitoneum black (as usual in herbivorous fishes). Camimstuma, 49. 

 aa. Air-bladder wholly above (dorsal) of the alimentary canal. 



C. Alimentary canal elongate, nuire tlnin twice leni:th of body; teeth one- 

 rowed, the grinding surface well developed, ih" hook usually slight 

 or wanting: peritoneum usually black. Species chiefly herbivorous. 

 ^ChunJrvstumiiue.) * 



