Jordan and Everman?i. — Fishes of North America. 1189 



browD, light below; dorsal, anal, aud ventrals dark. Galapagos Archi- 

 pelago ; scarce; the specimens here described from Charles Island, one of 

 the Galapagos, the largest about 18 inches long. The posterior half 

 of the body resembles that of the species of Faralabrax ; the long, low 

 head suggests Philypnns. (Named for Professor Louis Agassiz.) 



Cratinus ngtushii, Steindachnek, Ichth. Beitr., vii, 10, 1878, Galapagos Islands (Coll. Agas- 

 siz & Steindachncr); Jordan & Eigenmann, I. <•., ;i!)4, 1890. 

 SerraiiKs tujasshU, Boulenger, Cat., i, 282. 



507. HYPOPLECTRUS, Gill. 



(Vacas.) 



HitpopUch-UK, Gill, Pioc. Ac. Nat. Sci. Phila., 1862, 236, [imella). 



Body more deep and compressed than in the other groups allied to Ser- 

 ranus. The skull ditters from that of Serranus chiefly in the development 

 of the supraoccipital crest, which, in accordance with the form of the 

 body, is much elevated. The smooth area on top of cranium is large 

 extending backward to border of preopercle, the supraoccipital and pari- 

 etal crests being short; the ventrals, as in Serranus, are behind the axil 

 of the pectoral. All the species have several antrorse serrai on the lower 

 limb of the preopercle, but smaller than in Gonioplecirus. The species of 

 Eypoplectrns are all American, and a study of their relations offers many 

 difficulties. We have examined typical examples of a large number of 

 the nominal species. While each of these shows certain striking peculi- 

 arities in color, most of them are absolutely identical, one with another, 

 in all other respects. Moreover, even among those in which the coloration 

 seems most sharply defined, there are many variations. After an exami- 

 nation of the large series of typical forms sent by Professor Poey to the 

 Museum at Cambridge, we find ourselves driven to the conclusion that all 

 the common forms of Hypoplectrus probably constitute but a single species, 

 subject to almost endless variations in color. This view we here adopt, 

 leaving for convenience sake the various nominal species to stand as color 

 varieties or subspecies, produced by the action of some agencies as yet 

 unknown, (i'tto, below ; TrPij/fcrpoi, spur.) 



a. Scales large, aljout 46 pores in lateral line; body short and deep, the depth 214 in length; 

 head 2f; profile from dorsal to occiput convex, concave above eye; preorbital narrow; 

 maxillary reaching to below middle of eye; lower jaw slightly included; teeth strong, 

 large teeth in front J; fourth dorsal spine highest, 21 in head; middle caudal rays little 

 shorter than the outer ones; pectoral reaching anal; teeth of preopercle growing larger 

 downward; angle aud lower limb with about 9 strong radiating serra', those nearest 

 the angle largest, the others directed more and more forward. Color (of the single 

 specimen known) black with violet luster; faint, pale streaks along the rows of scales 

 on lower parts of bo'ly; caudal fiu abruptly translucent yellowish; pectorals colorless; 

 tips of dorsal and aual spines and edge of soft rays abruptly whitish. 



lAMPRURUS, 1579. 

 aa. Scales moderate, 60 to Go pores in the lateral line; dorsal rays X, 15; depth 2 to 234 "» 

 length, the head about 3; maxillary 2 in head; caudal fin slightly lunate; fourth dor- 

 sal spine highest, 2g in head; pectorals narrow, about reaching second anal spine; 

 gill rakers short and slender, x + 12. Coloration extremely various, characterizing 

 many nominal species or varieties described below. unicoloe, 1580. 



