388 PROCEEDINGS OF THE ACADEMY OF [1887. 



trils small, the posterior scarcely the larger, separated from the an- 

 terior by one diameter. Angle of preopercle scarcely salient, but 

 provided with coarser teeth ; a rather sharp notch above it. Gill 

 rakers moderate. X-|-18, Scales moderate, scarcely ctenoid. 



Dorsal spines low, the outline of the spinous dorsal gently con- 

 vex, the fourth spine longest, 3 in head. Soft dorsal high, its out- 

 line angular, the tenth ray produced, 31 in head. Anal fin formed 

 as in M. faleata, its seventh ray j^roduced, 2^ in head, its posterior 

 outline concave. Caudal subtruncate, the outer rays slightly pro- 

 duced. Pectoral If in head. 



Color in spirits plain dark olivaceous, the edges of the fins scarcely 

 darkei". 



Several specimens of this species from the Galapagos Islands are 

 in the Museum of Comparative Zoology. These were mixed with 

 specimens of the more common Mycteroperca olfax, from the same 

 locality. Other specimens (10061 M. C. Z.) are from Payta, Peru. 

 Mycteroperca xenarcha resembles M. olfax in form and color. In 

 M. olfax however, the nostrils are close together, the postei'ior some 

 three times the diameter of the anterior : the second and third dor- 

 sal spines are elevated, about half higher than the fourth. Both 

 species have the angular anal fin as in M. faleata, a character also 

 shown in less degree by M. acutirostris and 31. tigris. 



