14. HETERODONTID^ GYROPLEURODUS. 
33 
“111 the latter genus, the branches of the lower jaAr are at lirst con- 
tiguous and diverge from each other at an acute angle, while in front of 
the obh(iue whorls of molars, and between the acute teeth of the front 
which encroach on the sides, a cordiform area exists. The lateral or 
molar teeth are immeroiis, and arranged in obli(iiie whorls, Avhich raj)idly 
increase in size to the lifth, behind Avhich they again decrease. The 
branchial apertures are also comparatively large, the lirst being longer 
than the length of the branchial region. 
“In Gyropleio'odus, the branches of the lower JaAv are widely separated 
by an interval rounded in front and becoming Avider behind, the sides 
tliemselA'es being curved outwards; the acute teeth are couliued to 
the front and the molar teeth are few and disposed in about four Avhorls, 
the lirst three of Avhich slightly increase, while the fourth is almost 
rudimentary. The liranchial area is almost oblong.” 
Head short and high, broad, but Avith subA^ertical sides; the forehead 
very declivous from eyes, and Avith the snout Avide and transverse, but 
l)rominent; tAvo blunt, diA'crging ridges are continued from each side of 
the snout and abruptly merge into the more conspicuous superciliary 
ridges, the interA’al between which is nearly plane ; teeth in front digi- 
tated, Avitli three or four cusps, quincuncially distrilmted in roAvs slightly 
couA'crging tOAA’ard the middle; in the upper jaAA, on the sides, molars 
oblong and liattened, arranged in about four oblique AA'horls, imiform or 
increasing backAvard, except the last, which is smallest; on the sides of 
the lower jaAT, also, are molars oblong, Avith tlatteued crowns, and arranged 
in transversely obli«pie Aviioiis, but decreasing liackward {GUI). One 
si)eeies known. ring or Avhoii ; sid(t; tooth.) 
41 . i'B’asacBsci (Grd.) Gill. 
Dorsal tins considerably produced backward at their jAosterior angle; 
the compressed spine forming about half of the base of each tin ; anal 
till large, directed A'ery obliquely ba(*kAvards, reaching the root of caudal ; 
caudal tin forming about one fourth of the length; color broAvmisli, A’arie- 
gated Avith sparsely scattered small black spots all ov^er the body and 
fins. Ooast of California {GUI). 
(Cesfracion franciiioi Girard, Fror. Ac. Nat. Sci. Pliila. 1854, 196; Ccstracion franclsco 
Giiiitlier, viii, 416; Gill, Proc. Ac. Nat. Sci. Phila. 1862, 492.) 
Bull. Nat. Mus. No. 10 3 
