GILBERT AND STAEKS — FISHES OF PANAMA BAY 171 



310. Gobius soporator Cuvier ilk Valenciennes. 



The most abundant fish of the tide-pools among the rocks. 



311. Gobionellus sagittula (Gfmther). 



Not seen by us; the species was described from specimens taken on the 

 Pacific Coast of Central America, and has been recorded from Panama Bay by 

 Jordan (1885, p. 387) and by Boulenger (1899, p. 3; Kio Tuyra, Darien). 



312. Gobionellus microdon (Gilbert). 



Plate XXVIII, Fig. 51. 



This species has been known hitherto from two immature specimens taken 

 in a brackish lagoon a short distance south of Guaymas, in the Gulf of California. 

 We now report it from the Panama region, where two specimens were secured in 

 the Rio Grande, at Miraflores, a point entirely above the action of the tides. One 

 specimen is immature, only slightly larger than the types, the other is 113 mm. 

 long, apparently adult. These enable us to correct the original account of the 

 species in respect to the dentition and the coloration. 



The teeth are minute in both jaws. Those in the mandible are in a narrow 

 band, with the outer series very slightly enlarged, inserted on the extreme outer 

 edge of the jaw, and directed almost horizontally. They are not separated by an 

 interspace from the rest of the band. Those in the upper jaw are extremely 

 minute, in a wider band than those in the mandible, the outer series stronger than 

 the others, but scarcely longer. Here again, there is no interspace between the 

 stronger series and the rest of the band. In Q. sagittula, the upper jaw contains 

 an outer series of strong conical teeth, separated by a well-defined interspace from 

 a narrow inner series of small villiform teeth; the villiform band in mandible is 

 somewhat wider, of slightly coarser teeth, with an outer series less enlarged, and 

 with two or three pairs of strong conical teeth in the inner series next the 

 symphysis. 



Color in spirits: light greenish olive, the snout and interorbital region 

 brownish; a narrow black streak extending backward from eye; a second narrowly 

 V-shaped streak on opercle. A series of five to seven vertically oblong blotches 

 or bars on middle of sides. In the young specimen, these are distinctly band- 

 like, and reach nearly to upper and lower profiles of body. In the adult, they 

 are much shortened, and the anterior ones are obscure. Alternating with these 

 bars above, is a series of blotches extending half way to middle line of sides, becom- 

 ing confluent in the dorsal region with a brown reticulum which encloses variously- 

 shaped areas of the ground color. A series of three brown blotches occupies the 

 naked predorsal strip. 



Dorsals whitish, each with three or four irregular lengthwise streaks, slightly 

 looped from ray to ray. The caudal has a number of narrow cross-bars composed 

 of series of small spots on the membrane. Other fins are colorless, or nearly so. 

 A bright green spot is on the base of the tongue in life. 



