450 8PABID^. 



in the length of the head. Body uniform greenish, with golden longi- 

 tudinal streaka ; dorsal, anal, and ventral fins blackish ; axil blackish. 

 Atlantic coasts of the United States. 



a. Adult. New York. Pxirchased of Mr. Brandt as S. ovis. 

 h. Adult: skin. New York. From Dr. Pamell's Collection. 



c. Thirteen inches long : not good state. N. America. Purchased 



of Mr. Warwick. 



d. Adult : skin. From Gronov's Collection. 

 «. Adult : skeleton. Old Collection. 



Description. — This species appears to have been confounded with 

 ihe following North American fishes, which also exhibit a procum- 

 bent dorsal spine ; — 



1. With Sargus ovis, which has broad quadrilateral incisors. 



2. With Sargus rhomboides, which has moderately broad incisors, 

 each with a notch. 



3. Perhaps with Sargus aries (a more southern species), which has 

 the body marked with seven cross-bars. 



4. With Chrysophrys aculeatus, which, according to Valenciennes' 

 description, has three series of molars. In our species the anterior 

 incisors, although sufficiently flattened, are so narrow, that a super- 

 ficial observer might take them for conical canine-Hke teeth, as in 

 Chrysophrys. 



Our species, which I call ;S^. ambassis, from the recumbent spine 

 by which the genus Ambassis is distinguished, has the body elevated ; 

 its greatest depth is below the sixth dorsal spine, where it ia con- 

 tained 2| in the total length. The nape of the neck descends abruptly 

 in a somewhat irregular curve, whilst the upper profile of the head 

 is straight. The distance between the origin of the dorsal fin and 

 the occiput is shorter than the length from the occiput to the snout. 

 The length of the head is nearly one-fourth of the total ; the head 

 is rather compressed, the distance between the eyes being one-fourth 

 of the length of the head. The snout is elevated, rather pointed, and 

 slightly produced ; the pra;orbital is rhombic, as wide as high ; the 

 upper maxillary reaches to the vertical from the posterior nostril. 

 The eye is of moderate size, situated in the vertical from the occiput. 

 There are six series of scales between the prajorbital and the limb 

 of the prajoperculum, which is covered at the angle with a few 

 irregular scales besides ; th operculum has a narrow space along 

 its base scaleless, the remainoer is covered with scales like the sub- 

 and intcroperculum. The suprascapula is scale-like, striated, and 

 there is a curved series of similar scales ascending from the supra- 

 scapula to the nape. 



The dorsal fin begins above the opercular margin and extends to 

 the vertical from the 37th scale of the lateral line, its distance from 

 the caudal fin being equal to one-half the length of the head. The 

 spines are of moderate size and taper very much at their extremity : 

 the first is short ; the fourth is the longest, one-half the length of 

 the head; the following gradually decrease in length to the last, 

 which is five-eighths of the longest. The upper margin of the doraal 



