430 DE. GUNTHER OX THE FISHES OF CEMKAL AMEWCA. 



being two-fifths of that of the head. Caudal fin rounded, witli the middle rays pro- 

 duced. The second anal spine is truly spinous, not flexible, two-fifths of the length of 

 the first soft ray. INIembrane of the dorsal and anal fins not scaly. Tlie pectoral fin 

 extends as far backwards as the ventral, being more tlian half as long as the head. 

 Immaculate, silvery, back greenish. (Pseudobranchiiie present.) 



One specimen, 14^ inches long, was obtained by Mr. Salvin at C'hiapam. 



67. OtOLITHUS RETICULATUS. 

 (nuith. Froc. Zool. Soc. 1864, p. U9. 



1). IOI^tjjVt- a. 11(2.9). 



Closely allied to 0. caroUnensis. Scales rather irregularly arranged ; there are nine 

 series between the origin of the dorsal fin and the lateral line. The height of the body 

 is contained four times and a third in the total length (without caudal) ; the length of 

 the head thrice and a third. The extent of the snout is two-sevenths of the length of 

 the head ; the maxillary does not extend backwards to the vertical from the posterior 

 margin of the eye ; prseopercular angle somewhat produced behind, membranaceous, 

 striated ; the posterior margin of the prscoperculum obliquely descending backwards. 

 The spinous dorsal is much longer than high ; its spines are feeble, tlie fourth being 

 the longest, two-fifths of the length of the head. Caudal fin subtruncated, the middle 

 rays somewhat produced. The first anal ray is quite rudimentary ; the second as long 

 as the eye, flexible, scarcely spinous. The pectoral fin extends as far backwards as the 

 ventral, being more than half as long as the head. Back and sides with an irregular 

 network of brown undulated streaks ; fins immaculate. 



Two specimens were collected by Mr. Salvin — one, 15 inches long, at San Jose, the 

 other, 13 inches long, at Chiapam. 



71. Caraxx leucurus. 



Giiuth. Proc. Zool. Soc. 1864, p. 24. 

 ^'ery closely allied to C. bicolor. 



The first dorsal fin is composed of short, stoutish spines, the fourth of which is the 

 longest, but scarcely longer than the eye. The soft dorsal and anal are rather elevated ; 

 the caudal is eraarginate, and has the lobes rounded. Teeth very small, forming a 

 single series in both jaws ; palate smooth. The height of the body is one-half of the 

 total length (without caudal), the length of the head one-third. Snout rather obtuse, 

 the jaws being equal in front when the mouth is closed ; the maxillary extends to 

 below the anterior margin of the orbit. The lateral line makes anteriorly a subsemi- 

 circular curve, the width of which is contained from once and two-thirds to once and 

 four-fifths in the length of the straight portion ; it becomes straight behind the vertical 



