6 ACANTHOPTERYGII. 
1881, p. 232‘, and 1882, pp. 368 *, 372°, 377", and 380°; Jord. & Everm. Bull. U.S. Nat. 
Mus. xlvii. 1898, p. 2195’. 
Eleotris lembus, Giinth. Cat. Fish. i. p. 121 (1861)”. 
Eleotris lateralis, Giiuth. t. c. p. 122". 
Gobiomorus lateralis, Eigenm. & Fordice, Proc. Ac. Philad. 1885, p. 69°; Jord. & Eigenm. Proc. 
U.S. Nat. Mus. 1886, p. 482°; Eigenm. & Eigenm. Proc. Cal. Ac. (2) i. 1888, p. 51”. 
Gobiomorus maculatus, Eigenm. & Fordice, t. c. p. 70”. 
Philypnus dormitor (part.), Meek, Zool. Pub. Columbian Mus. v. 1904, p. 226°. 
Depth of body 32 to 5 in the length, length of the head 23 to 3. 55 to 60 scales in a longitudinal series, 
20 to 24 from interorbital region to origin of anterior dorsal. Dorsal VI, 19. Anal 110. Caudal 
peduncle 14 to 2 as long as deep. Body usually spotted or marbled with dark brownish and with a more 
or less distinct dark longitudinal band from eye to base of caudal; an oblique dark stripe from eye 
across the preorbital ; a vertical stripe from eye to corner of mouth; a dark spot on the upper part of 
the base of pectoral ; soft vertical fins with or without series of small dark spots on the interradial 
membranes, sometimes with series of light spots. 
Hab. Pacific Coast Rivers from California to Ecuador: 
Cape St. Lucas? 45.—Rio Presidio®; Colima®; Tehuantepec !*; San José® ; 
Panama ‘.—Ecuador ! 2 19, 
Here described from six specimens, 128 to 215 mm. in total length, from Presidio 
and Ecuador, including the types of the species. 
This species has the head and body more compressed than its Atlantic congener, 
and has constantly a ray more in the anal fin. 
2. ELEOTRIS, Gronow, 1763. 
Guavina and Eleotris, Jord. & Everm. Bull. U.S. Nat. Mus. xlvil. 1898, pp. 2198 & 2199. 
Body elongate, subcylindrical, more or less compressed posteriorly ; head broad, more or less depressed. 
Mouth large, oblique; lower jaw projecting ; jaws with small pointed teeth in bands; palate toothless. 
Eyes rather small; interorbital region broad. Gill-openings moderately wide, extending forward to 
below the angle of preeoperculum, the gill-membranes attached to the isthmus. Scales small or moderate, 
ctenoid or cycloid; no lateral line. Two dorsals, with VI-VI1, I 7-13 rays; anal with I 7-13 rays ; 
caudal rounded; pectoral symmetrical, rounded; ventrals well separated, each with a short feeble spine 
and 5 branched rays. 
This widely distributed tropical genus comprises several species, some of which are 
strictly marine, whilst some enter rivers, and others appear to be permanently 
fluviatile. The three species which are known to occur in the rivers of Mexico and 
Central America may be distinguished thus :— 
I. D. VU,110. A.110. 95 to 110 scales in a longitudinal series ; no preeoper- 
cular spine Be ee 
Il. D. VL 18 <A.18. 55 to 70 scales in a longitudinal series ; a small concealed 
antrorse spine at the angle of the przoperculum. 
Depth of body 4 to 48 in the length . 2. 2. 1. 1 ww ew 1 ww. 2 pisonis. 
Depth of body 5to6inthe length . . . . . . 1. 1... 8 pita. 
1. guavina. 
