22 Papers from the Department of Marine Biology. 



Apogonichthys stellatus Cope. 



Three specimens, 1.5 to 2.5 cm. long. Inhabits dead sea-urchin shells. 

 Almost every sea-urchin skeleton in small muddy area west of Guanica Har- 

 bor was inhabited by one of these delicate little fishes. The individual was never 

 found more than a foot or two away from its shelter and when disturbed or 

 approached darted into the shell. At low tide or when the surf was breaking 

 over the mud flats the fish was invariably found inside the shell. 



Measurements of the largest individual are as follows: Depth 3; head 2.7; 

 eye 3; snout 5; scales 2-27-6. The chromatophores take the form of stel- 

 lations in spirit preparations. In life this fish is a uniform dark brown, almost 

 black, with no evidence of bars or spots. 



No. 3048, Zoological Museum, Princeton University. 



CENTROPOMID^E. 



Centropomus pectinatus Poey. 



One specimen, about 20 cm. long, from Guanica Lake. 



SPARID^E. 

 Diplodus argenteus (Cuvier and Valenciennes). 



From coral reef off Guanica Harbor. 



SCI^ENID^J. 



Eques pulcher Steindachner. 



One specimen, 5 cm. long, from cluster of coral rock in shallow water west 

 of Guanica Harbor. 



No. 3097, Zoological Museum, Princeton University. 



POMACENTRIDjE. 



Microspathodon niveatus (Poey). Plate 4, fig. 1. 



Head 2.7; 3.4 in total length. Depth 1.7; 2.5 in total. Eye 2.5; snout 3. 

 Dorsal XII, 15; anal II, 13. Scales 3-25+6-10. Mouth small; max- 

 illary reaching to nostril. Upper teeth small, movable; lower teeth twice 

 as large and more or less fixed. 



Color in life uniform deep marine-blue with about 35 pure-white silvery 

 spots, each the size of a scale, covering the entire body. More numerous on 

 dorsal fin and dorsal part of head and body. When seen in the sunlight these 

 spots reflect light and appear like so many points of fire. 



Many specimens of this beautiful fish were seen swimming among the 

 corals of the western end of Rajos de la Parda; they varied in length from 

 about 2 to 4 inches. The color was the same in all. Only one specimen was 

 obtained, 2.12 inches long, from which the above description was taken. 



No. 3099, Zoological Museum, Princeton University. 



Microspathodon chrysurus (Cuvier and Valenciennes). 



Several specimens observed on the coral reefs off Guanica Harbor, but none 

 were obtained. 



Microspathodon fowleri sp. nov. Plate 4, fig. 2. 



Head 3.2; depth 1.87. Dorsal XII, 15. Anal II, 13. Scales 3-29+7-10, 

 21 pores. Eye 3.9. Body compressed, but rounded; profile from snout to 

 dorsal evenly rounded ; slight indication of fleshy crest at nape in 1 individ- 



