333 bulletin: museum of comparative zoology. 



Heliaster polybrachius. 



H. L. Clark, 1907. Bull. M. C. Z., 51, p. 64. 



Plate 7, figure 1. 



This interesting starfish is remarkable for its very limited range, as it is known 

 only from Zorritos, Payta, and the Lobos de Afuera Islands. The number of rays 

 ranges from 31 to 43 and averages rather more than 37. The largest specimen 

 seen is about 180 mm. across. Nothing is recorded of the color in life, but pre- 

 served specimens are dull greenish or blackish above, often marked with yellowish 

 blotches; rarely the yellowish predominates; spines and actinal surface yellowish. 

 Two specimens in the Coker collection were taken on the shore rocks of Lobos 

 de Afuera, March 27, 1907. 



Heliaster helianthus. 



Asterias helianthus J. B. P. Lamarck, 1816. Anim. s. Vert., 2, p. 558. 



Asterias {Heliaster) helianthus J. E. Gray, 1840. Ann. Mag. Nat. Hist., 6, p. 179. 



Heliaster helianthus F. Dujardin et Hupe, 1862. Hist. Nat. Zooph. Ech., p. 344. 



Plate 7, figure 3. 



Meyen (1834) speaks of this as the " ausgezeichnetesten " species of starfish 

 and it certainly must always rank as one of the most notable species, because of its 

 large size (300 mm. in diameter) and numerous rays (30-40). It ranges from 

 northern Ecuador (about 2° N. lat.) to Valparaiso, and seems to be very com- 

 mon, as it has been recorded by all collectors on that coast. Dr. Coker took speci- 

 mens at the Lobos de Afuera Islands, on the northeast side of San Lorenzo Island, 

 at the Pescadores Islands, and at Independencia Bay, south of Pisco. Of the 

 last, he says in his field notes, " white below ; above black with spines red." So 

 far as I can discover this is the only observation on the color of a living Heliaster 

 which has ever been recorded, and it shows that the dull shades (blackish and 

 yellowish) of preserved specimens give no clue to tiie fine coloration of the living 

 starfish. 



Brittle-Stars. Ophiuroidea. 



The brittle-stars comprise an astonishingly small part of the Peruvian 

 fauna, especially when it is remembered that not less than thirty species 

 occur at Panama, most of which might reasonably be expected to occur 

 as far south as Payta. While lack of attractive reefs and bottoms may 

 account for the absence of some species, it is probable that more inten- 

 sive collecting will increase the number considerably. The ten species 

 herein recorded represent seven genera, none of which is characteristic of 

 the region ; all but one or two are cosmopolitan. Yet, strangely enough, 

 five of the species are not known outside of the Chile-Peruvian region, 



