WEST INDIAN STARFISHES 27 



Family Zoroasterid^ Sladen. 



Zoroasteridw Sladen, op. cit., pp. xxxvi, 416, 1889. Perrier, Exped. Trav. 

 et Talisman, p. 112, 1894. Ludwig, op. cit., 1905, p. 159. 



Disk small ; rays long and slender, angular or rounded. 



The disk is covered largely by the ten enlarged basal radials 

 and interradials, and the large central plate. 



A row of large overlapping carinal plates stiffens the rays, each 

 usually bearing a spine. Marginal plates scarcely differentiated 

 from the dorso-laterals and interactinals. 



All these form close, regular, imbricated, longitudinal rows, 

 often six to eight proximally. They are also imbricated in trans- 

 verse rows. 



All the plates are granulated or finely spinulose and the lateral 

 and interactinal rows usually bear, also, a single elongated 

 spine, and usually a dermal major pedicellaria. Papular pores 

 are single and placed between all the rows of plates. 



Adambulacral plates are alternately unlike. The larger are 

 compressed, carinate, and project far into the groove. They bear 

 a divergent row of several spines transverse to the groove, and 

 have one or two small spines in the groove. The alternate small 

 plates do not project into the groove, are not carinate, and bear 

 fewer spines. Spines of both kinds of plates may bear large 

 major pediceUariae. 



Minor or crossed pedicellarise appear to be lacking. Sucker- 

 feet are in four rows proximally, becoming reduced to two rows 

 distally. Their suckers are small. 



This is essentially a deep-sea family. Only a few species have 

 occurred in less than 150 fathoms. 



Genus Zoroaster Thomson. 



Zoroaster W, Thomson, Depths of the Sea, p, 154, 1873. Sladen, op. cit., 

 p. 416, 1889. Perrier, op. cit., 1894, p. 115. Fisher, op. cit., 1911b, p. 



The central plate of the disk has few smaller plates around it. 

 The basal radials are prominent, but not much larger than the 

 next radials and of the same character. The basal interradials 

 are smaller and flatter, without a central spine. The central plate 

 and basal and median radials have a central short articulated 

 spine. The whole surface is covered with a rather thick dermis 

 and with small articulated spinules, attached to basal papillae. 



