THE FISHES OF PORTO RICO. 
109 
another short ridge on anterior part of operole at level of lower part of eye; opercles very convex, as 
if swollen outward; keels on body and tail all strong, the two lateral keels on body terminating on third 
caudal ring; the two lateral keels on tail beginning on last body ring, thus overlapping body keels; 
median keel on side well developed, terminating on sixteenth body ring; ventral keels strong; 
abdominal keel very strong. Egg-sac on first 18 caudal rings. 
Color, yellowish-brown, with darker punctulations; tip of snout white; cheek, throat, and under 
parts of snout white, crossed by about 7 or 8 irregular brownish bars extending downward and back- 
ward; opercles brown; fins pale. 
This species is related to C. albirostre, of Heckel, differing from it chiefly in the shorter snout, 
smaller dorsal, and fewer rings. It is known only from Key West and Porto Rico. A fine female, 4 
inches long, was seined on Cayo Jancudo, at Fajardo, February 17. 
Corythroichthys cayorum Evermann & Kendall, Bull. U. S. P. C. 1897 (Peb. 7, 1898) , 128, pi. 7, fig. 7, near Crawfish Bar, 
Key West, Fla.; Jordan & Evermann, l.c., 2838,1898. 
Genus 42. HIPPOCAMPUS Rafinesque. The Sea-horses. 
Body strongly compressed, belly gibbous, tapering abruptly to a long, quadrangular, prehensile 
tail. Head with a distinct curved neck placed nearly at a right angle with direction of the body, 
surmounted by a compressed occipital crest, on top of which is an angular, star-shaped coronet ; top and 
sides of 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 body each with 6 spines or 
tubercles, those of tail with 4. Pectoral fins present, short and broad; anal minute, usually present; 
dorsal fin moderate, opposite the vent. Egg-pouch in male a sac at base of tail, terminating near vent. 
Species numerous in all warm seas. They attach themselves by their tails to seaweed and other 
floating substances, and are often carried to great distances by currents. 
a. Dorsal fin large, with 19 rays; rings 11 + 32 to 35; depth of body equals length of head; snout 2.33 in head; dorsal fin 
on 3.5 -|- 0 rings; body mottled, not dotted hudsonius 
aa. Dorsal fin smaller, with 16 to 18 rays. 
b. Dorsal fin with 17 or 18 rays, on 1 caudal ring; snout short, less than half length of head; light-blue spots on head 
and snout; head usually without filaments; size large punctulatus, 62 
bb. Dorsal fin with 16 rays, on 4 + 0 rings; rings 12 + 31; snout longer than postocular distance; body unspotted; size 
moderate stylifer 
aaa. Dorsal fin very small, with 12 rays, on 2 + 1 rings; rings 11 + 30; snout very short; body without white spots., zosterse 
62. Hippocampus punctulatus Guichenot. Sea-horse; Cabalito de Mar. 
I). 18, covering 21 -| 1 rings; rings 1 2 -f- 30. Snout short, about 2.6 in head, or slightly shorter 
than postorbital part of head; eye 2 in snout; supraorbital spines divergent, each with a minute spine 
in front; coronet high, about 1.5 in snout; no filament on coronet, and only a few very short ones any- 
where on head, none on body; spines of body strong, but blunt. 
Color, dark-brown, fins pale; head with numerous minute white specks; body and tail with a 
few similar specks. 
Found in the tropical parts of the Atlantic; common in the West Indies, Brazil, and western 
Africa, reaching occasionally northward in the Gulf Stream as far as Beaufort, N. C. (Jenkins. ) One 
specimen, about 3 inches long, seined at Ponce, January 30. 
Hippocampus punctulatus Guichenot, in Sagra’s Cuba, Poiss., 174, pi. 5, fig. 2, 1860, Cuba; Poey, Fauna Puerto-Riquena. 
347,1881; Stahl, 1. c., 79 and 165, 1883; Jordan & Evermann, 1. c., 777, 1896. 
Hippocampus marginalis Keckel, in Kaup’s Lophobr., 15, 1856, Mexico. 
Hippocampus fascicularis Heckel, in Kaup’s Lophobr., 15, 1856, Mexico. 
Hippocampus longirostris Heckel, in Kaup’s Lophobr., 12, 1856; not of Cuvier. 
Hippocampus gvttulatus Gunther, Cat., VIII, 202, 1870; probably not of Cuvier. 
? Hippocampus kuda Bleeker, Nat. Tyds. Ned. Ind., Ill, 82, East Indies. 
Family XXV III. ATHERINIDyE. The Silversides. 
Body rather elongate, somewhat covered with scales of moderate or small size, which are usually, 
but not always, cycloid. No lateral line; some scales often with rudimentary mucous tubes. Cleft of 
the mouth moderate. Teeth small, on jaws and sometimes on vomer and palatines, rarely wanting. 
Premaxillaries protractile or not. Opercular bones without spines or serrature. Gill-openings wide, 
