THE FISHES OF PORTO RICO. 
293 
m all, the only differences being very minor ones in the height of certain crests. Gobius oceanicus seems 
most aberrant, but is difficult to separate generically on account of intermediate forms. Probably 
several of the many genera indicated by Bleeker will prove valid, but only a thorough study of 
skeletons can establish them. It is not unlikely that Clenogobius, to which group most of our species 
belong, may be separable from Gobius. 
Gobius: 
a. Upper rays of pectoral fin. silk-like; i. e., short and very slender and flexible, free for nearly their whole length. 
b. Body robust, compressed posteriorly soporator, 247 
Ctenogobius: 
aa. Upper rays of pectoral normal, not silk-like, similar to others. 
c. Scales large, 25 to 33. Color in life olivaceous, more or less spotted, never red. 
d. Dorsal soft rays 12 to 14; vertex and nape with a slight median fold of skin. Body long, not much compressed; 
head 3.5; eye 3 in head; a dark spot on first dorsal eigenmanni 
dd. Dorsal soft rays 10 to 12. 
e. Caudal with 2 spots at its base; jaws unequal, lower slightly produced; body robust, compressed behind, depth 5 in 
total length; head 4.33; eye longer than snout, 3.5 in head; maxillary reaching pupil; teeth in a band, the 
outer enlarged and distant, the inner enlarged and bent backward. Brownish; a faint blue spot on each scale; 
six spots along middle of back; similar spots on scapular region and middle of side; a dark spot above opercle; 
blue dots on head; a straight blue line crossing cheek above and continued on opercle; dorsals faintly 
spotted. D. vi-10; A. 10. Scales 25,-7 glaucofrsenum 
ee. Caudal plain or with but a single spot at its base. 
/. Dorsal spines low, highest little longer than head. 
g. Region from nape to dorsal entirely scaled. 
h. Pores on preopercle not very conspicuous; no canine teeth. Body subfusiform, little compressed; depth 4.5 in 
length; head blunt, 4 in length, rounded in profile; eye equal to snout, 4 in head. Mouth small, horizontal, 
lower jaw included; maxillary 3 in head, reaching to below eye. Teeth small, in bands in both jaws, the 
outer enlarged, those of upper jaw very slender. Scales large, ctenoid, those of nape and belly little reduced. 
Longest dorsal spine shorter than head. Caudal scarcely pointed, about as long as head. Color, whitish-gray, 
middle of side with 4 or 5 dark blotches, from each of which a narrow dark bar extends downward and 
forward; a large black blotch above pectoral, obsolete in female; a small black spot at base of caudal; a dark 
mark below eye; vertical fins barred. D. vi-12; A. 11 or 12. Scales 33 sligmaturus 
hh. Pores on preopercle very conspicuous; lower jaw with small canines. D.vi-i, 9; A. i,9 quadriporus 
gg. Region between nape and dorsal with a narrow naked median strip. Body moderately elongate, subfusiform, 
depth 5.33 in length. Head large, not so blunt as in G. boleosoma, 3.4 to 3.66 in length; anterior profile gently 
decurved; snout 3.33 to 3.5 in head; eye 4; mouth large, slightly oblique; maxillary extending to front of pupil, 
2.33 in head. Teeth small, slender and curved, in moderate bands. Scales moderate, ctenoid, those in front 
much reduced in size; breast naked. Longest dorsal spine 1.5 in head. Caudal as long as head, somewhat 
pointed. Olivaceous, mottled with gray; about 5 rounded dark blotches along middle of side, last forming a 
spot at base of caudal; no dark spot on side of nape; some dark marks on head; vertical fins barred. D. vi-12; 
A. 13. Scales 33 to 35 shufeldti 
ggg. Region between nape and dorsal entirely naked. 
i. Highest rays of second dorsal little more than half head, none of them reaching base of caudal. ; 
j. Profile much decurved, skull rounded behind, without distinct median ridge; mouth horizontal. Body elongate, 
deepest below front of dorsal, tapering regularly backward, greatest depth 5.5 in length. Head short, blunt, 
profile anteriorly abruptly decurved, cheek somewhat swollen. Length of head 3.5 in body. Snout about equal 
to eye, 3.66 in head. Mouthhorizontal, maxillary reaching to below pupil (in male) ; lower jaw included. Teeth 
in each jaw in a band, outer row of upper jaw large, recurved. Scales large, ctenoid, somewhat reduced ante- 
riorly. Nape, breast, and belly naked. Dorsal spines about two-thirds of head. Caudal pointed, 2.66 to 3.5 in 
body. Color olivaceous, with numerous dark reticulations on back; 5 black spots along side, the Iasi forming 
a spot on base of caudal, sometimes with V-shaped dark bars extending from them to dorsal; breast and sides 
of belly with numerous dark specks in male; a dark line between eyes; a dark line from eye to middle of pre- 
maxillary, some dark spots below eye, sometimes forming bars, sometimes a stripe; a large oblique spot above 
pectoral, continued on opercle; a black spot at base of pectoral: dorsals and caudal barred, anal uniform 
dusky, ventrals and pectoral black in male, white in female. D. VI-11; A. 10 to 12. Scales 25 to 30. . boleosoma 
jj. Profile moderately decurved; eye longer than snout, 3.75 in head. Color yellowish, oblong dark blotches on 
middle of side; dorsal and caudal barred. Head 4; depth 6. D. vi-12: A. 10 faseialus 
ii. Highest rays of second dorsal as long as head, the last reaching base of caudal. Body elongate, back not arched; 
depth 6 in length; head 4, not compressed, cheek tumid. Profile abruptly decurved, the snout 3.33 in head. 
Mouth large, nearly horizontal, maxillary reaching posterior edge of eye in males, middle of eye in females. 
Teeth in narrow bands in each jaw, outer somewhat enlarged, outer'in some (males?) much enlarged above 
and recurved, enlarged teeth fixed, others movable. Scales large, ctenoid, reduced anteriorly, belly naked. 
Dorsal spines little filamentous, longest about equal to head; caudal 2.25 to 3 in body. Males dark-olive, with 
4 oblong dark blotches along middle of side; a dark caudal spot; a black blotch larger than eye on each side 
of shoulder; dorsal spotted; caudal reddish above, dusky below; females with 5 oblong dark blotches on side 
the last on base of caudal; from each of middle blotches a V-shaped bar runs to back; a black shoulder blotch, 
a dark bar from eye to mouth; ventrals pale, with 2 dark streaks. D. vi-11; A. 12. Scales 30 (27 to 33) at leasi 
in males. eiicseomus 
