598 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



as I.utkeu coucludes, there probably are but two species, distinguished 

 by diifereut fin-formulse. If the fins have become hardened or dried by 

 exposure or by being immersed in too strong alcohol, it is impossible to 

 obtain the correct count except by dissection. 



G. hippurus is very abundant off our South Atlantic coast in summer, 

 being caught south of Cape Hatteras by coast steamers on nearly every 

 trip. Korth of the cape it is said to be rarely taken . Tlie species reaches 

 a length of 4 or 5 feet. 



When first caught, the head, body, and tail, are greenish olive, or dark 

 greenish olive-brown, lighter below; a series of about 15 round blue 

 spots on back along each side of base of dorsal, these placed at nearly 

 uniform distances apart, and about one-third size of pupil ; sides below 

 with numerous blue spots irregular in size, shape, and position, but none 

 of them so large as those along back; lower lip largely blue ; about three 

 concentric blue lines around snout above. Dorsal jmrplish blue, with 

 irregular areas of lighter and darker, and with some greenish reflections; 

 in one sp''cimen the dorsal and caudal are sparsely covered with blue 

 spots similar to those on body. Caudal yellow ; anal yellowish, with 

 translucent border; pectorals translucent, with brownish axil ; ventrals 

 outwardly greenish olive, within of an indeterminate dark brownish, 

 with olive cast. The play of color in the dying dolphin has been largely 

 exaggerated, judging from our own observation. Such change as there 

 is, seems to consist in the apparent rapid development of an external 

 bright silvery pigment, with some blue and green reflections, this de- 

 velopment being accompanied with partial restorations of the ground 

 color, thus afibrdiug some real play of shades, which are, however, not 

 l^rilliant. At death the fish is largely silvery, the intense deep lustrous 

 blue of the spots remaining meanwhile unchanged ; afterwards appear 

 large irregular patches of the ground color, yellowish on sides, yellow- 

 ish olive-brown on back. 



D. 59 to G3 ; A. 20. 



Head little elevated, its lieight at origin of dorsal 1^ to I4 in its 

 length ; maxillary scarcely reaching middle of orbit, 2 J in head; teeth 

 recurved, in broad cardiform j)atches, those on vomer uniform, the 

 patches on jaws and palatines with an external series of larger conical 

 teerli. Eye of in head, 1| in snout. Head 4| in length to base of cau- 

 dal ; depth 5. Dorsal beginning slightly in advance of posterior margin 

 of orbit ; the longest ray about | snout, slightly more than J head ; upper 

 lobe of caudal 3| in body. Ventral inserted slightly posterior to base 

 of upper pectoral ray, its length l\ in head, less Mian in body; pec- 

 toral H in head, 7 in body. 



60. Centrarcluis macropterus (Lac.) Jor. 



Many young specimens of this species, with the ocellated dorsal spot 

 very conspicuous, are in the Charleston Museum, from Black Eiver, 

 Soutli Carolina. 



