STARFISHES OF THE PHIIJPPINE SEAS. 475 



Remarks. — The type of this species (or perhaps subspecies) is much 

 larger than that of Z. alfredi^ which measured R, 190 mm., and in 

 which E, equals 9 r. A specimen of ophiactis from station 5648 has 

 R 120 mm. and R=12 r. Thus the ray is relatively longer than in 

 alfredi, while in the type of ophiactis the ray is relatively twice as 

 long, but the specimen is much larger. Alcock describes the disk 

 pedicellariae of alfredi as being as large as grape stones. This is 

 certainly very much larger than in ophiactis^ where the longest, nar- 

 rowly lanceolate as viewed from the side, measure 2 mm. They 

 are usually about 1.5 mm. long. As for the pedicellariae of the rays, 

 Alcock says that they are much more conspicuous than any of the 

 spines except those on the plates of the 2 most actinal rows. This 

 is not true for ophiactis. The pedicellariae are not so long as the 

 spinelets, as a rule, and those which are longer than the spinelets 

 are too slender to be very conspicuous. The stout carinal spines are 

 much heavier than those of alfredi and much larger than any of 

 the pedicellariae. There seems to be considerable difference in the 

 details of the adambulacral armature. 



Z. alfredi was dredged in the Bay of Bengal 1,300 to 1,380 fathoms, 

 Globigerina ooze. 



ZOROASTER MICROPORUS Fisher. 



Plate 134, fig. 4, 4a ; plate 136, fig. 2 ; plate 139, fig. 4. 



Zoroaster microporus Fishee, 1916&, p. 30. 



Diagnosis. — Related to Zoroaster harathri Alcock, from which it 

 differs in having squarish instead of hexagonal carinal plates, smaller 

 miliary spinelets, longer central spines on 5 lateral rows of plates 

 (instead of on the 2 or 3 lowermost series only), more numerous 

 pedicellariae, in having 2 inner spines of the prominent adambu- 

 lacrals with pedicellariae (3 in harathri?)^ and in having 2 

 transverse series of spines on the actinal face of both sorts of 

 adambulacrals. R=205 mm., r=12 mm., R=:17 r; breadth of ray at 

 base, 13 mm. Disk small, scarcely more than the united bases of the 

 rays ; rays long, slender, with a conspicuous, rounded, unarmed cari- 

 nal ridge, and a well-defined sulcus along either side; 5 series of 

 lateral plates with a central spine ; tube feet biserial. 



Description. — Major portion of abactinal surface of disk occupied 

 by primary apical plates, forming 2 circles around the large tumid 

 central plate (see figure). Plates covered with short papilliform 

 spinelets spaced about half to two-thirds their length, the calcareous 

 portion slender, but their membranous investment giving them an 

 ovoid, often asymmetrical, form. No enlarged central spines. Two- 

 jawed pedicellariae, slightly longer than the spinelets, rather numer- 

 ous around the papulae and along the sutural lines. Papulae 1 or 2 



