64 U.S. NATIONAL MUSEUM BULLETIN 2 02 Vol. 2 



black; pectorals pale; small round intensely black spot on upper edge 

 of pectoral base not extending below the base of third ray (more dis- 

 tinct in specimens of 40 to 60 mm. than in smaller ones). 



Remarks. — This species has been considered a synonym of D. 

 marginatus (Riippell, Atlas zu der Reise im nordlichen Afrika . . . 

 Fische des rothen Meers, p. 38, pi. 8, fig. 2, 1828) by many authors 

 (see Fowler, Mem. Bishop Mus., vol. 10, p. 306, 1928, Fowler and 

 Bean, 1928, Montaiban, Bur. Sci. Manila Monogr. 24, p. 24, 1927, 

 Weber and Beaufort, Fishes of the Indo-Australian Archipelago, 

 vol, 8, p. 465, 1940), but we conclude it is distinct (see pi. 81, A). We 

 have carefully compared specimens from the Marshall and Philip- 

 pine Islands with those of comparable size from Zanzibar, as well as 

 with Riippell's figure, and find them to be distinctly different in 

 coloration. D. marginatus does not possess a dark vertical bar from 

 dorsal origin through pectoral base to pelvic base, but instead has a 

 large dark area (this may be lacking in some preserved specimens) 

 covering entire nape and upper anterior sides downward and back- 

 ward, fading behind pectoral, as clearly shown in Riippell's figure 

 though not in that of Cuvier and Valenciennes (Histoire naturelle des 

 poissons, vol. 5, p. 437, pi. 133, 1830); pectoral base blackish except 

 opposite lov/er2 or 3 rays; furthermore, the general ground color of 

 our specimens from Zanzibar is dark greenish brown as stated by 

 Cuvier and Valenciennes and these specimens have small brown dots 

 in middle of scale bases, the scales are not dark margined as in D. 

 reticulatus. 



Giinther (Catalogue of the fishes in the British Museum, vol. 4, 

 p. 14, 1862), who had specimens of marginatus from Riippell's collec- 

 tion, noticed these differences and separated the two species, discussing 

 one under D. xanthosoma Bleeker and including a discussion of 

 Heliases reticulatus Richardson pointing out that the type specimens 

 of the latter appear to be lost. 



DASCYLLUS TRIMACULATUS (Rappell) 



Plate 82,A,E 



Pomacentrus trimaculaivs RiipPEhh, Atlas zu der Reise im nordlichen Afrika . . . 



Fische des rothen Meers, p. 39, pi. 8, fig. 3, 1828 (type localitj', Massaua, 



Red Sea). 

 Dascyllus triniaculatus Kendall and Goldsborough, Mem. Mus. Comp. Zool. 



vol. 26, p. 298, 1911 (Jaluit, Marshall Islands). 



SPECIMENS STUDIED 



Rongelap Atoll: 1 station, 1 specimen, 57 mm. standard length. 

 Jaluit Atoll: Albatross, 1 specimen, 93 mm. 

 Arno Atoll: 1 lot, 1 specimen, 44 mm. 

 Guam: 1 lot, 1 specimen. 



