776 Bulletin 47, United States National Museum. 



Body strongly compressed, the belly gibbous, tapering abruptly to a 

 long, quadrangular, prehensile tail. Head with a distinct curved neck, 

 placed nearly at a right angle with the direction of the body, surmounted 

 by a compressed occipital crest, on the top of which is an angular, star- 

 shaped coronet ; top and sides of the head with spines. Physiognomy 

 remarkably horse-like, like that of a conventional "knight" at chess. 

 Body and tail covered with bony plates, forming rings, those on the 

 body each with six spines or tubercles, those of the tail with 4. Pec- 

 toral fins present, short and broad ; anal minute, usually present ; dorsal 

 fin moderate, opposite the vent. Egg pouch in the male a sac at the base of 

 the tail, terminating near the vent. Species numerous, in all warnr seas. 

 They attach themselves by their tails to seaweed and other floating sul)- 

 stances, and are often carried to great distances by currents. {ItrnoKafiTzo^, 

 the ancient name, from Iktto^, horse ; Kd/niToc, a wriggling sea monster, 

 or a caterpillar.) 



a. Dorsal fin large, with 19 rays. 



h. Rings 10 + 38 ; slender, the tail longer than head and body ; hody unicolor or sparsely 



dotted with white. ingens, 1140. 



(*. Rings 11 + 32 to 35 ; depth of body equals length of head ; snout 2>3 in head ; dorsal 



fin on 3?.^ + rings ; body mottled, notdjtted. hudsonius, 1141. 



aa. Dorsal fin smaller, with 16 to 18 rays. 



c Dorsal fin with 17 or 18 rays, on 2 caudal rings ; snout short, less than half length 

 of head ; light-blue spots on heiid and snout ; head usually without filaments; 

 size large. puncttjlatus, 1142. 



cc. Dorsal fin with 16 rays, on 4 + rings ; rings 12 -|- 31 ; snout longer than post- 

 ocular distance ; body unspotted ; size moderate. st\'LIFF.r, 1143. 

 aaa. Dorsal fin very small, with 12 rays, on 2 -f 1 rings ; rings 11 + 30 ; snout very short ; 

 hody without white spots. zoster*, 1144. 



lUO. HIPPOCAMPUS INGENS, Girard. 

 (CaBALLITO DEI, JIar.) 



D. 19, on 3 -f 2 rings ; A. 4. Rings 11 + 36 to 38 ; eye moderate, 2i in 

 snout, which is 2J to 2J- in head, rather than opercle. Body in male 

 rather slender, its greatest depth in males I3 in head, or about e jual to 

 the distance from snout to posterior margin of orbit ; tail longer than 

 head and body together. Spines on head and body high, with large 

 fringed flaps; supraorbital spine nearly half diameter of eye ; coronet 

 well developed, with five spines ; surface of plates with many small 

 papilla^, each third to fifth tubercle of dorsal series enlarged; shoulder 

 girdle Avith 3 tubercles; anterior spine of frontal triangle much lower 

 than the others; female more slender, the depth If in head, the snout 

 equal to rest of head. Color blackish, usually plain, faintly barred with 

 darker ; papilhe on body pale, giving an appearance of scattered whitish 



Uippoc-mipii.'i anliqiionni), Leach, Zoiil. Misc., 1814, 104 ; GCnther, Cat., viii, 200, 1870. 

 Hippocampus Irevimslris, CuviER, Regne Anim., Ed. 11, 1829, Venice ; after Willughbv ; figure 



of a fresh specimen. 

 Hippocampus gultatiis, Cuvier, I.e.; also after Willuqhbv, the type apparently from Venice, a 



specimen dried and straightened out. 

 Hippocampus anliquua of authors. 



