Fishes of Massachusetts. 297 
contained a specimen of the Leuciscus crysoleucas 
more than five inches in length. 
The color is a silvery gray: in very large speci- 
mens, all the upper part of the body, as well as the 
head and fins, are of a rusty black. Length of 
head, compared to that of body, as 1 to 4: depth 
of body across base of pectorals, four inches and 
two lines. Upper jaw protractile: very fine teeth, 
thickly set in both jaws. Eyes large, pupils black, 
irides silvery. Nostrils double, posterior nearly as - 
large again as the anterior. Operculum, preoper- 
culum and maxillary bones covered with scales. 
Head back of, and between eyes, scaly. The space 
between nostrils, and in front of eyes to maxillary 
bones, destitute of scales. Preoperculum, dentic- 
ulated behind and below; denticulations much 
smaller upon the upper portion of posterior edge. 
The lowest edge of operculum very slightly serra- 
ted; a spine at its posterior angle, and above this 
an obtuse point. The lateral line commences at 
the upper posterior portion of the operculum, and 
inclining a little upward, is lost on the membrane 
connecting the middle rays of the caudal fin. 
The first Dorsal fin commences about six lines 
back of the base of the pectorals, and is about half 
as high as long. 
The second Dorsal fin is rather more than two 
thirds the length of the first dorsal: its first ray is 
spinous. 
The Pectorals commence on a line with the pos- 
terior angle of the operculum: length equal to one 
third their height. 
VOL. IIL.—-NO. III. 20 
