JORDAN ON FISHES OF THE KIO GRANDE OF TEXAS. 667 

 Dacentrus lucens, gen. et sp. nov. 



I find four more specimens of the small Labroid fish referred to on 

 page 399. These are larger and in better condition than the first one, 

 and I have been enabled to examine the lower ijharyngeals of one of 

 them. These I find to be nnited, as usnal in this group, into a broad 

 triangular bone, in which I am uuable to fiud a median suture. This 

 bone is covered with rather large, close-set, bluntish -conical teeth. As 

 the lateral line is complete, and the scales cycloid, I place this fish, 

 among the Lahridw, rather than among the Clchlidco, but I am entirely 

 unable to locate it among the genera of that family known to me. In- 

 deed, I find no description of any species on our coasts to which it bears 

 any special resemblance. Although taken in fresh waters, and occur- 

 ring in a collection of fresh-water species, it is very likely a salt-water 

 fish. The present notice is rather to call attention to this fish than to 

 complete its history. In describing the species, I make at present no 

 attempt to separate its generic from its specific characters. The ety- 

 mology of Dacentrus is 8a, an intensive particle ; xevrpw, a spine, in spe- 

 cial allusion to the long second spine of the anal fin. Body ovate* 

 strongly compressed, the form Sunfish-like, much as in the genus Cen- 

 trarchus, the depth being contained (in young of less than 2 inches) 2J 

 times in the length. Head large, moderately pointed, its length 2^ 

 times in that of the body, its upper outline concurrent with that of the 

 back, not making an angle with it; mouth not large, the jaws about 

 equal, the maxillary not reaching to the front of the orbit; upper jaw 

 quite protractile; the lips not very fleshy; teeth in jaws moderate, 

 conical, apparently in a single series ; eye large, 3 in head, its position 

 rather anterior; cheeks with three rows of rather large, silvery scales; 

 opercles in all my specimens bare and silvery ; none of the opercular 

 bones serrated ; gill rakers pretty long and slender, rather closely set. 

 Branchiostegals uncertain, probably five. 



Scales rather large, silvery, cycloid ; their number about 5-37-11. 

 Lateral line running high up, concurrent with the back, continuous, not 

 interrupted or deflected, very distinct. 



Fin-rays: — Dorsal, about XVIII, 10; anal, III, 20, or thereabouts; 

 ventrals, I, o ; spinous portion of dorsal much longer than the soft part, 

 the spines gradually increasing in height to about the sixth, then more 

 gradually diminishing, the highest spine a little less than half the length 

 of the head. Along the base of the spinous dorsal is a sheath of rather 

 large silvery scales. Anal spines somewhat curved, the second spine 

 considerably longer than the first and third. Pectoral fins barely reach- 

 ing anal; ventral fins rather short; caudal fin so broken that its form 

 cannot be ascertained. 



Colors obliterated. The typical specimens are silvery, darker above, 

 without distinct markings anywhere. There are five of these, varying 

 in length from 1^ to If inches. They are doubtless the young of some 

 fish which reaches a considerable size. 



