186 BULLETIN 189, UNITED STATES NATIONAL MUSEUM 



spine a little longer than the third and fifth, about the same length 

 as the longest soft rays, 2.4 in head; caudal rather gently concave, 

 the angles somewhat produced, the upper one somewhat longer than 

 the lower; anal small, the third spine scarcely longer or stronger than 

 the second, the latter 4.3 in head; ventral large, inserted under base 

 of pectoral, its spine 4.3 in head; pectoral long, reaching little be- 

 yond tip of ventral, with obliquely rounded margin, the fourth to 

 sixth rays counting downward being the longest, 1.3 in head, 4.1 in 

 length. 



Color grayish brown, somewhat darker above than below ; side and 

 back indefinitely blotched with light and dark areas; occiput with a 

 few pale spots, with dark rings and dark centers; a large dark area on 

 opercle; dorsal pale brown, membrane behind each spine narrowly 

 margined with black, soft part with suggestions of slightly darker 

 spots; caudal brown, with suggestions of dark spots on upper lobe; 

 anal and pectoral plain translucent; ventral largely dusky. 



The description is based on the type (U.S.N.M. No. 77624), 300 

 mm. (245 mm. to base of caudal) long, taken at Paita by R. E. Coker. 



Figure 42. — Diplectrum maximum, new species. From the type, 300 mm. long, Paita, 



Peru (U.S.N.M. No. 77624). 



It is the largest specimen reported as D. conceptione by Evermann and 

 and Radcliff e (see reference above) . This specimen differs from those 

 herein described as D. conceptione in having a notably longer and more 

 pointed snout, with a much more prominently projecting lower jaw, 

 the tip of which is in line with the dorsal outline of the snout. The 

 gill rakers on the lower limb of the first arch are fewer, the angle of 

 the preopercle is much more strongly produced, and a larger number 

 of spines is enlarged with the middle ones much less divergent. It 

 is known that the preopercular spines change somewhat with age in 

 some of the other species, but the changes noticed are not compara- 

 ble with the differences between this large specimen and the smaller 

 ones of D. conceptione at hand. The pectoral fin is differently 

 shaped, the fourth to the sixth rays being the longest, instead of the 

 sixth and seventh; there are two more oblique rows of scales on the 

 cheek, and two fewer scales in an oblique row from opercular spine 

 to margin of preopercle. 



