2342 Bulletin 47, United States National Museum. 



times in length of body; eye small, its diameter about -J interorbital 

 width; opercular spine well developed; ventral disk nearly as long as 

 head; mouth rather small, anterior, maxillary reaching front of eye; inci- 

 sors of lower jaw nearly horizontal, rather broad, 3-lobed at tip, the 

 middle cusp the longest; upper teeth much smaller, the median ones 

 compressed, blunt, close set, a little shorter than the lateral teeth and 

 with dentate edges, 1 or 2 series of small teeth close behind them ; anal 

 beginning under middle of dorsal; the distance from insertion of dorsal 

 to base of caudal contained 3 in length; pectoral as long as head; 

 caudal truncate, with rounded angles. Back with 5 dark cross bars about 

 as wide as -the interspaces, 3 of them in front of dorsal fin, the 2 anterior 

 much broader and more distinct than the others; these bars all dis- 

 tinct on back, fading on sides, which are often vaguely clouded with 

 dark; the color of these dark bars varies from reddish brown to black, 

 and that of the interspaces from olivaceous to light pink and bright rose 

 red; top of head bright red, marbled with light slaty bluish; a black 

 blotch on opercle, and 2 very distinct black cross spots, 1 on each side of 

 median line, forming the front of first dorsal bar; cheek sometimes with 

 2 or 3 pale bluish streaks ; dorsal, pectoral, and caudal more or less shaded 

 with dusky; lower fins pale; usually a dark bar at base of caudal and 

 1 across middle of fin; shade of ground color extremely variable.* Very 

 abundant in the rocky tide pools around Mazatlan, hiding everywhere 

 under the numerous sea-urchins, especially Arbacia stellata, the protective 

 coloration of both being that of the Corallina, which lines the rock pools. 

 Length 2 to 3 inches, (zebra, from the banded coloration.) 



Gobiesox zebra, JORDAN & GILBERT, Proc. U. S. Nat. Mus. 1881, 359, Mazatlan, Mexico 

 (Type, No. 29250. Coll. Gilbert) ; JORDAN & GILBERT, Bull. U. S. Fish Comm. 1882, 

 108 ; JORDAN, Proc. Cal. Ac. Sci. 1895, 499. 



* The following note on the variations is furnished by Miss Susan B. Bristol: 

 " J find 4 specimens of this species which differ considerably from the typical form. 

 These may represent a distinct species, but at present we are inclined to think that all 

 these forms are modifications of one species, Arbaciosa zebra. The following is a descrip- 

 tion of a specimen 1J inches long, taken at Mazatlan (No. 4166 in the L. S. Jr. Univ. Mu- 

 seum): Head 3$; depth 9. D. 5 or 6; A. 6. Body slender, much depressed, compressed 

 posteriorly, the greatest width 4| in length. Head depressed, its width 1| in its length. 

 Eye very small, about 1 in interorbital width. Snout rather rounded, 3 in head. ( )per- 

 cular spine present. Interorbital width 2 in head. Ventral disk If m head Mouth 

 small, the lower jaw inferior; outer teeth in both jaws serrate. Anal beginning at end 

 of the first of dorsal. Distance from fmnt of dorsal to base of caudal 1 in head. Cau- 

 dal terminate. Pectoral 2| in head. Color bright red, with very irregular yellow mot- 

 tlings on back and sides, light yellow below; back with 4 irregular dark-red 'cross bars, 

 the posterior 3 of which are wider than the interspaces ; 3 of the cross bars in front of the 

 dorsal fin, and the fourth on either side of the dorsal; 2 conspicuous black spots about 

 i as large as eye, 1 on either side of median line on back above the pectorals a short 

 distance behind their origin; snout plain, dark red; pupil white; 2 yellow parallel 

 stripes extending from eye backward and downward, the second ending at a point about 

 * the distance from tip of snout to end of opercle; dorsal, caudal, and anal dusky; ven- 

 trals and pectorals paler; a large red blotch at base of pectorals extending for a consid- 

 erable distance on the fin. Another specimen from Mazatlan, bright red in color, about 

 | of an inch long (also in bottle No. 4166, L. S. Jr. Univ. Museum), differs from the preceding 

 form in the following respects : In tire greater depth, which is 6f in length, in the smaller 

 ventral disk, which is 1 in head; in the more pointed snout; in the absence of the 2 

 black spots above pectorals ; and in having the 4 dark red bands on the back more dis- 

 tinctly marked. Two specimens from Guaymas, Mexico, 1 and 1 J inches long, No. 92 in 

 the L. S. Jr. Univ. Museum, are chocolate brown in color, the shorter having on its back, 

 including the bar at base of caudal, 7 dark brown cross bars and no dark spots above the 

 pectoral, while in the longer there are no cross bars but a dark brown spot about \ as 

 large as the eye is present above the pectoral; also, in the longer one, the dorsal begins 

 at the end of first third of anal. The eye in the larger specimens of zebra is larger than 

 m these 4 specimens, but some of the smaller specimens seem to be intermediate in this 

 regard between the typical form and these forms," 



