ASTEROIDEA "9 



Type locality. Challenger St. 313, near the Atlantic entrance to the Strait of 

 Magellan, 55 fathoms, sand; bottom temperature 47-8° F. 



Distribution. Falkland Plateau, Burdwood Bank; Gulf of California; southern 

 Alaska to southern part of Bering Sea; 55-245 fathoms. 



Notioceramus gen.nov. 



Diagnosis. Resembling Peltaster Verrill in having the entire surface covered with 

 granules and the abactinal plates of radial papular areas without an elevated tabulum ; 

 differing from Peltaster in having short adambulacral plates with 2 (1-3) coarse furrow 

 spines and a shorter but heavier subambulacral spine, followed by i or 2 smaller 

 tubercles; pedicellariae primitive, composed of 3 flattened granules. 



Type Notioceramus anomalus. 



Remarks. The type species is represented by only one specimen. Its abactinal 

 surface resembles that oi Peltaster micropeltus^ (Fisher), but there the resemblance ends, 

 for in micropeltus the adambulacral plates are longer than broad, with a furrow series of 

 5 or 6 small spines (rather like those of Ceramaster) and 2 longiseries of small granules 

 (3 or 4 in first series, 5 or 6 in the outermost). Abactinally there are rather numerous 

 small upright two-jawed spoon-shaped pedicellariae about the size of the granules. The 

 jaws are often curved. 



The adambulacral armature of Peltaster is of the type of Ceramaster, in which there is 

 typically a gradation in length from the furrow spines through 2 or 3 series of successively 

 shorter granules to the actinal granulation. In Notioceramus the armature can more 

 appropriately be compared to that of Cladaster and Hippasteria. In fact, the armature is 

 similar to that of certain plates of H.falklandica, at about mid R, even to the form of the 

 subambulacral spines, except that in the latter species unequal granules occupy the 

 transverse and outer margins of the plates. 



In Progoniaster Doderlein,^ in which all the plates are granulated, the adambulacral 

 armature is similar to that of Peltaster. The only specimen of P. atavus is probably 



immature. 



Notioceramus anomalus sp.nov. 



(Fig. D, i-ie; Plate II, fig. 4; Plate IV, fig. 5) 

 Diagnosis. General form pentagonal, produced into short slender rays ; disk low, 

 scarcely inflated, but rays convex dorsally ; margins bevelled and rounded ; entire animal 

 covered with rather coarse, close-set granules ; abactinal plates rather small, not tabulate, 

 with 6-8 granules on plates of radial series, diminishing as to size, regularity, and 

 number of granules toward margin; marginal plates 17; adambulacrals with 2 (proxim- 

 ally sometimes 3, distally usually i) coarse furrow spines, a still heavier subambulacral, 



1 Tosia {Ceramaster) micropetta Fisher, 1906^, p. 1054, pi. 21, fig. 2; pi. 26, figs. 4, 4a; 313-8°° fathoms, 

 off Bird Island, Hawaiian Islands. This species was later assigned to Peltaster (Fisher, 191 1 , p. 205) but it is not 

 typical, although it has numerous furrow spines and subambulacral granules. 



2 D6derlein, Die Asteriden der Liboga-Expedition, Pentagonasteridae, 1924, p. 61, pi. 17, figs. 3-3C. 



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