Jordan and Evernia?in. — F is lies of N'orth America. 1203 



510. DIPLECTRUM, Holbrook. 

 (Squirrel-kisiiks.) 



liijihclriiiii, HiiLBROOK, Ichtliyolojiy of Soutli Carolina, Ed. 1, a2, 1850, {f(iiicicularis=fiirniosut). 

 llalilicicit. Gill, Proc. Ac. Nat. Sci. Phila., 18(>2, 230, (hicUlalus -- radialii', and other species; 



rostriit.d to biviltatiis by Joutjan & Gilbert, Synopsis, .WS). 

 Pnraaerraims, Bleeker, Verb. Akad. Ainst., xiv, 1873, G, (ItasseHi). 



This genus is very close to Prionodcs, from which it differs chietiy iu 

 the armature of the preopercle, which is provided in the adult with 1 

 or 2 clusters of strong, straight, divergent spines. Smooth area on top 

 of head, as in Scrranus, large, extending backward to a line connecting 

 borders of preopercle ; the supraoccipital and parietal crests very short ; 

 preorbital broad ; maxillary widest before its tip ; profileof snout rounded; 

 pectoral unsymmetrically rounded, its upper rays longest; ventrals 

 inserted * somewhat before axil of pectoral; dorsal spines slender, none 

 of them much elevated ; soft dorsal short, the rays X, 12 ; anal rays III, 7 ; 

 caudal lunate. Species all American, of small size and bright colors. 

 ((5/f, two; 7rAr//crpov, spur.) 



Haliperca (aA?, sea; wepKij, perch): 



II. Preopercle with a siogle center of divergence of the spinulcs axnit its angle (in tln^ adult 



as well as in the young). 

 h. Gill rakers yery long, slender, and numerous, about 25 below angle of arch; scales on 

 cheek in 7 or S rows; preopercular process narrow and truucato, its width about J^ 

 head; no black within gill cover; a pale-blue streak below orbit; about 18 scales 

 before dorsal; head with opercular flap about 3 in body. sciURrs, 1590. 



bb. Gill rakers moderate, about 10 below angle of arch; spines on produced portion of pre- 

 opercle numerous, 8 to 20 in number; outline of the spinous dorsal (iu somewhat con- 

 vex, so that the fin is more deeply notched than in Diplectrum formomm; jaws ecjual; 

 vertex naked; opercio black within." 

 c. Scales on checks small and regularly placed, in about 10 rows; 22 scales beforo dorsal; 

 head short, with opercular tlap about 3 in body; width of preopercular process 4>^ 

 to 5 in head, its posterior edge rounded; gill rakers x f 10, short and slender, 

 well separated; region above the large eyo prominent; snout short, bluntish; 

 _cheeks with 10 rows of scales; these regularly placed; serrw on preopercle much 

 produced in the adult, short in the young; upper lobe of caudal little produced. 

 Color light brown above, dull yellowish below; the scales on sides each with a 

 silvery center; irregular, vague, dark cross bars, broader than the interspaces; a 

 black bar at ba?e of caudal; usually no blue Hues or white areas on head; soft 

 dorsal with bright-blue spots, each surrounded by a dark-bluo ring; caudal with 

 bars of similar spots; young with 2 black longitudinal stripes, the lower forming 

 a spot at base of caudal. raiualk, 1591. 



cc. Scales on cheek large, irregular, in 5 or G rows; head larger; soft dorsal pale below, 

 mottled above, without distinct blue spots; 15 to 17 scales before dorsal. 

 (2. Head moderate, 2% in total length, with opercular flap; width of preopercular pro- 

 cess 34 head, its posterior edge truncated; upper edge of preopercle nearer tip of 

 opercular flap than snout; brownish, with numerous traces of vague, dark cross 

 bars; a very distinct black caudal spot; snout with 4 or 5 pale blotches; a pale 

 streak from below eye across preopercular angle; no black at base of soft dorsal, 

 the fin with very faint traces of blue spots. mackopoma, 1592. 



<bl. Head very large, 2V, to 2',^ in total length (with opercular flap); upi>er angle of 

 preopercle midway between tip of snout and tip of opercular flap; preopercu- 

 lar process very broad; soft dorsal dark at base. euryplectrum, 1593. 



^'Essentially as iu CentroprMif, nut as in Serrami^, in which these species are placed by I>r. 

 Bouleuijcr. 



