342 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



found this species off the northeast side of San Lorenzo Island, near Callao ; in 

 Ancon Bay, on a muddy bottom, 9 fathoms, and also among shells and sea-weed ; 

 and in the Bay of Sechura in 5 fathoms. There are no notes in regard to appear- 

 ance or habits. 



Ophiothrix magnifica. 



T. Lyman, 1868. Proc. Boston Soc. Nat. Hist., 7, p. 254. 

 Plate 9, figure 4. 



This handsome brittle-star is known only from the coast of Peru, between Payta 

 and Callao, arid from the Galapagos Islands. It grows to a fairly large size, the 

 disc 10-15 mm. in diameter, the arms 50-75 mm. long. Like most species of the 

 genus the color is more or less variable ; in preserved specimens it varies from 

 light gray to dark blue ; the radial shields may be mottled with very dark and 

 very light shades, almost black and white, or the inner half of the shield may be 

 dark and the outer half white ; in some specimens a longitudinal white stripe on 

 the upper surface of the arm is faintly indicated. Dr. Coker met with this species 

 only in the Bay of Sechura. From a comparison of many specimens of magnifica 

 collected at Payta, with a still larger series of the following species (spiculata) 

 from a number of localities, I have reached the conclusion that the two forms 

 intergrade so completely that they are probably identical. As such a question can 

 much better be decided from fresh or living material, it has seemed best to keep 

 the two forms separate. 



Ophiothrix spiculata. 

 J. Le Conte, 1851. Proc. Philadelphia Acad. Nat. Sci., 5, p. 318. 



This is a common and wide-spread Panamic species, somewhat smaller than the 

 preceding and more variable in color. Dr. Coker took it in the Bay of Sechura 

 and near Capon, and it has also been taken at Payta and Zorritos. The specimens 

 in the Coker collection from Capon were found living in a sponge, but nothing 

 else is noted as to habits. 



Gorgonocephalus panamensis, 



Astrophyton panamense A. E. Verrill, 1867. Trans. Conn. Acad., 1, p. 251. 

 Gorgonocephalus panamensit T. Lyman, 1882. Kept. voy. " Challenger," 5, p. 264. 



According to Verrill (1. c.), this species ranges from La Paz, Mexico, to Zorri- 

 tos, Peru, but it was not met with by Dr. Coker. The size of an adult is, disc 

 35 mm. in diameter, arms 140-150 mm. long. The color of dried specimens is 

 yellowish brown. 



Sea-Urchins. Bchinoidea. 



The sea-urchins rank next to the star-fishes both in number of species 

 found on the Peruvian ceast and in number of species characteristic of 



