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BULLETIN OF THE UNITED STATES FISH COMMISSION. 
form; they are slightly arched, the convexity being directed toward the pharyngeal cavity, tapering 
anteriorly, and broad posteriorly. They are coated with a thick, soft membrane, which reaches far 
beyond the margin of the bone and is studded all over with minute horny cilia. Each branchial arch 
is provided with a series of long gillrakers, which are laterally bent downward, each series closely 
fitting to the sides of the adjoining arch; they constitute together a sieve admirably adapted to permit 
a transit for the water, retaining at the same time every solid substance in the cavity of the pharynx.” 
Of the 5 genera occurring in American waters, only 2 are represented in Porto Rico. 
MUGILIN.E: 
a. Stomach muscular, gizzard-like: teeth slender, usually having the form of cilia; lower jaw angular in front; .species 
chiefly marine. 
b. Anal spines 3: teeth ciliform, flexible. 
c. Orbit with a well-developed adipose eyelid, covering part of iris; cilia in one or few series, slender; cleft of mouth 
chiefly anterior Mugil, 44 
bb Anal spines 2, first soft ray simple but articulate; teeth distinct, in a few series, scarcely ciliform, often obsolete in 
lower jaw; lips thin; no adipose eyelid; preorbital serrate Quekimana 
Agonostomin,®: 
aa. Stomach not gizzard-like: teeth not ciliform, lower jaw not angular in front; cleft of mouth lateral; fresh-water 
species, inhabiting chiefly mountain torrents in the Tropics. 
d. Teeth in villi form bands. 
e. Anal spines 2; teeth in bands on jaws and vomer; lower jaw without lamelliform folds Agonostomus, 45 
dd. Teeth coarse, broad, truncate incisors, with their free edges serrate; smaller teeth on vomer; none on palatines; 
head heavy, the blunt, tumid snout overhanging the small, inferior mouth; lower jaw forming a sharp soft 
edge Joturus 
Genus 44. MUGIL (Artedi) Linnaeus. The Mullets. 
Body oblong, somewhat compressed, covered with large scales. Head large, convex, scaled on 
sides and above. Mouth small, subinferior, the lower jaw angulated. Jaws with one or a few series 
of short, flexible, ciliform teeth; no teeth on vomer or palatines. Eye large, with a large adipose 
eyelid, which is little developed in the young. Stomach muscular, like the gizzard of a fowl. 
Species very numerous, living on mud and running in great schools along the shores and in 
brackish lagoons of all warm regions. 
a. Soft dorsal and anal fins almost naked; anal rays in, 8, rarely in, 7; sides with dark longitudinal stripes along 
rows of scales; caudal deeply forked, size large. 
b. Scales about 33 in longitudinal series: depth about 4.5 in length to base of caudal, teeth very minute; distance from 
tip of pectoral to front of dorsal about two-sevenths the length of pectoral; lips rather thin brasiliensis, 66 
bb. Scales about 41 in a longitudinal series; depth about 4 in length to base of caudal; teeth close-set, rather small; 
distance of tip of pectoral from front of dorsal about two-ninths the length of pectoral cephalus 
aa. Soft dorsal and anal fins scaled, sides without dark stripes along rows of scales; caudal less deeply forked; size 
smaller. 
c Anal rays in, 9. scales 35 to 45 in a longitudinal series. 
d. Scales 42 to 45 in longitudinal series: teeth small incilis 
dd. Scales 35 to 38 in longitudinal “eries. 
c. Pectoral not nearly reaching origin of dorsal, distance from its tip to front of dorsal being in the adult one-sixth 
length of pectoral; teeth close-set, rather small, but distinctly visible without a lens; scales 38 or 39 in longi- 
tudinal series; dorsal less falcate curema, 67 
ee. Pectoral nearly reaching origin of dorsal; scales 35 or 36 in longitudinal series; bare space between dentary bones 
small gaimardianus 
cc. Anal rays lit, 8: scales very large, about 33 in a longitudinal series: teeth wide-set, larger than in any other species 
except selosus , about as long as nostril; upper lip thick; pectoral not nearly reaching front of dorsal; size 
small trickodon, 68 
66. Mugil brasiliensis (Agassiz). “Liza”; Mullet; Lebrancho. 
Head 4; depth 5; eye 5.75; snout 4.5; interorbital 2; D. iv-i, 8; A. in, 8; scales 35-12. 
Body long and slender, more so than in any other of our species; snout broad, blunt, and evenly 
rounded; profile from snout to dorsal fin almost straight; ventral outline somewhat more convex; top 
of head nearly flat; upper lip thin; preorbital large, almost covering maxillary; eye hidden in front 
and behind by a broad adipose membrane; teeth minute; scales large, about 21 between tip of snout 
and origin of spinous dorsal; soft dorsal and anal almost naked, caudal covered with line scales at base; 
margin of soft dorsal and anal very concave; caudal deeply forked, the lobes equal, about as long as 
head; pectoral moderate, one-sixth in head, not reaching origin of spinous dorsal by a distance greater 
than diameter of eye; ventrals slightly shorter than pectoral. 
