526 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



^ KEY TO THE SPECIES OF ASTROSTEPHANE HEREIN DESCRIBED. 



a\ Rays 16, with prominent, complete costae and 1 to 3, usually 3, conspicu- 

 ous intercostal bands of pedicellariae ; disk medium sized, with abruptly 

 rounded (not beveled) margin; actinostome relatively very large; 1 sub- 

 oral spine to each mouth plate ; disk plates with solitary spinelets only ; 

 lateral spines equal in length to 5 or 6 consecutive adambulacral plates; 



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adambulacral ai*mature t-t— or ^^t- moluccana, p. 526. 



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a\ Rays 11, with about 20 complete prominent costae and 1 complete and 1 or 2 



incomplete bands of intercostal pedicellariae ; disk decidedly small, with a 



beveled margin; actinostome relatively small; 2 large suboral spines to 



each mouth plate; disk plates with 1, 2, and 3 small spinelets in about 



equal numbers ; lateral spines equal in length to 7 or 8 consecutive adam- 



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 bulacral plates ; adambulacral armature jt:j acanthogenys, p. 52S. 



ASTROSTEPHANE MOLUCCANA Fisher. 



Plate 147, figs. 1, 2 ; plate 149, fig. 3 ; plate 154, figs. 2, 2a-c ; plate 156, figs. 2, 2a. 



Brisinga moluccana Fishek, 1916&, p. 32. 



Astrostephane moluccana Fisher, 1917/, pp. 421, 422, figs. 3 and 4. 



DiagTwsis. — Kays 16. Costae 25, complete, prominent, well-spaced, 

 with 1 to 3 intercostal bands of pedicellariae; costal spinelets rela- 

 tively coarse; disk medium, with isolated, papilliform, small spine- 

 lets, and minute pedicellariae; adambulacral plates about as wide 



as long, proximally; armature typically .——^ or ^r^- Costal area 



swollen, occupying somewhat more than basal third of ray ; integu- 

 ment thin, devoid of prickles. Breadth of disk=5 times width 

 of ray at base (6 mm.); actinostome=3^ times same; height of 

 disk=breadth of ray at base. R=410 mm., r=15 mm. (ray perfect, 

 with long attenuate extremity). 



Description. — Disk medium sized, with abruptly rounded margin; 

 abactinal integument fairly thin. The spaced, granuliforni abactinal 

 plates each with 1 papilliform spinelet about 0.5 mm. long, or less, 

 the calcareous part of which is delicate and sharp. The investment 

 gives the spinelets a stubby cylindrical form; some appear to be 

 scarcely longer than granules. Around the base of each are 5 or 6 

 very minute pedicellariae. The spinelets around the anal aperture 

 are longer than the others. 



Rays swollen throughout costal region, which occupies more than 

 a third and less than a half the length of ray. Costae, about 25, ver}^ 

 prominent, well spaced (for half or a third width of ray). They 

 are all complete, being opposite alternate adambulacrals and are 

 frequently bent or bowed aborad. Between them are from 1 to 3, 

 usually 3, broad, conspicuous bands of minute pedicellariae, which 

 are continued beyond the costal region, slightly more frequently than 



