1864.] DR. A. GUNTHER ON GUATEMALAN FISHES. 145 
We take here the opportunity of describing another species of this 
genus, the typical specimen of which is in the British Museum. 
CENTROPOMUS BREVIS. 
A. 3/6. L. lat. 50. Eight longitudinal series of scales between 
the origin of the second dorsal fin and the lateral line. The height 
of the body is two-sevenths of the total length (without caudal) ; the 
length of the head two-fifths. Preeorbital strongly serrated; sub- 
operculum produced into a long flap, which extends beyond the ver- 
tical from the origin of the dorsal fin. The intermaxillary extends 
to below the middle of the orbit. Dorsal spines strong ; the third is 
scarcely longer than the fourth, its length being equal to the distance 
between the hinder margin of the orbit and the extremity of the 
lower jaw. The second anal spine is very long, considerably longer 
than the third, and two-thirds of the length of the head; if laid 
backwards, it extends beyond the root of the caudal. The length 
of the ventral fin is two-thirds of the distance of its base from the 
origin of the anal. Vent much nearer to the anal than to the ven- 
tral. Lateral line greyish. 
We have only one specimen, 6 inches long, of this species ; we do 
not know from what part of Tropical America it comes. 
CENTROPRISTIS MACROPOMA. 
D. ue A. > L. lat. 52. IL. transv. 6/16. 
Closely allied to C. radialis, Q. & G.; but whilst that species has 
a notch above the spiniferous angle, the present has its preeopercular 
margin not interrupted, the long spines of the angle gradually pass- 
ing into the finer serrature. There are six series of scales between 
the eye and the angle of the preeoperculum. The maxillary extends 
nearly to the vertical from the posterior margin of the orbit. Dorsal 
fin with a notch, the ninth spine being considerably shorter than 
the tenth. A series of rather small brownish spots above and below 
the lateral line. 
Three specimens were collected by Messrs. Dow and Salvin on 
the Pacific coast of Panama. 
MESOPRION ARATUS. 
D. > AS .. L. lat. 45. LL. transv. 4/12. 
The height of the body equals the length of the head, and is con- 
tained thrice and two-fifths in the total (without caudal). The 
maxillary does not extend backwards to the vertical from the centre 
of the eye. Preeoperculum finely serrated, with scarcely a trace of 
a posterior notch. Dorsal spines of moderate strength; the third 
and fourth are the longest, two-fifths of the length of the head ; the 
eleventh is scarcely longer than the tenth, which is rather more than 
half as long as the fourth. Caudal fin emarginate, two-thirds scaly ; 
anal spines short, rather feeble, the third longer than the second, 
and equal in length to the last dorsal spine. Upper and lateral parts 
Proc. Zoou. Soc.—1864, No. X. 
