NEW FISHES 



20I 



Interorbital space a little wider than diameter of eye. Suborbital 

 gradually decreasing in width as it curves upward and backward below 

 eye; inferior margin with irregular serrations. Upper limb of pre- 

 opercle a little inclined backward from angle ; serrature well developed, 

 obsolete at angle. Several conspicuously enlarged scales on the opercle, 

 one very large one above base of pectoral ; twenty-five oblique scale 

 rows on body. Lateral line continuous, crossing the first nineteen 

 rows of scales, ends below middle of soft dorsal. 



Color in Alcohol. — Brown, paler on caudal fin and peduncle ; lips 

 dark like rest of head; posterior borders of scales of body darker, 

 forming dusky vertical stripes ; a distinct black spot on upper edge of 

 base of pectoral, not in axil. 



Variations. — The preceding description of the type applies almost 

 without change to the other adult specimens. In some, the upper limb 

 of the posterior preopercular margin is inclined backward more than 

 in the type, while in others it is less so, being in some almost vertical. 



Young Specimens. — One immature specimen 72 mm. long has the 

 anterior upper profile somewhat rounded, resembling in this respect 

 E. arcifrons. Another 60 mm. long, however, has the profile the 

 same as in the adults. These specimens, especially the smaller one, 

 have the caudal peduncle, basal part of caudal fin, posterior part of 

 body back of middle of soft dorsal, and posterior half of soft dorsal 

 pale orange. In all ages the spot on the base of the pectoral is very 

 distinct. In the specimen which is 60 mm. in length one scale on 

 the back of the caudal peduncle is dusky posteriori}', forming a rather 

 prominent mark on the prevailing yellow color. 



There is no trace of spots on the scales of any of the specimens. 



The species is known only from Clarion, Socorro and San Benedicto 

 Islands of the Revillagigedo Archipelago. 



MEASUREMENTS OF Poniaccntrus redctnptus. 



Length in mm 



Depth 



Head 



Pectoral 



Ventral 



Eye : Head 



Interorbital: Head 



Preorbital : Head 



Dorsal Spines 



Second Dorsal Rays .... 



Second Anal Rays 



Scale Rows 



Scales on Lateral Line. 



60 

 50 

 30 

 28 



37 

 33 

 28 



15 

 XII 



15 

 13 

 25 

 20 



