STARFISHES OF THE PHILIPPINE SEAS. 505 



GeniiS ODINIA Perrier. 



Odinia Pekrier, Ann. sci. nat., Zool., vol. 19, art. 8, 1885, p. 9. Type, 0. 

 semicoronata Perrier. 



ODINIA PENICHRA Fisher. 



Plate 142, fig. 1 ; plate 151, figs. 3. 3«-c. 



Odinia penichra Fisher, IQlQh, p. 31. 



Diagnosis. — Eays 16. Eays rather slender, the costal region ex- 

 tending about half the length of ray and containing 10 to 12 com- 

 plete, rather weak, conspicuously spiniferous costae, widely and 

 nearly equidistantly spaced; disk with steeply beveled margin and 

 conspicuous, terminally denticulate spinelets in ones and twos on 

 its slightly convex plates; adambulacral armature with 1 slender 

 aboral furrow spinelet and 1 actinal spine proximally bifid; oral 

 plates with 4 or 5 actinostomial spinelets, and 1 aboral furrow spine- 

 let; no suboral spine. E=100 mm., r=7.5 mm. (to edge of disk), 

 R=13.3 r; breadth of ray at base, 3.5 mm.; breadth of actinostome, 

 9 mm. 



Description. — Disk with a beveled margin and closely placed, 

 slightly convex, plates bearing usually 1, but sometimes 2 or 3 

 slender, tapering, spaced spinelets one-half to once their length apart 

 and about 0.75 nun. in length. The tip of the spine consists of 

 several very minute points, and there is usually a tiny pedicellaria 

 at the base. Papulae conspicuous and distributed all over disk. 



Eays slender, only slightly inflated at base, and with 10-12 com- 

 f)lete, rather weak, widely spaced costae, extending nearly half the 

 length of ray. Beyond these are 3 or 4 rudimentary costae hidden 

 by pedicellariae. The first costa is about one-third the diameter 

 of disk from the base, and the first 6 or 7 intercostal spaces are paved 

 with irregular contiguous plates, becoming disconnected in the 7th 

 and 8th spaces. Scattered plates of the first 2 intercostal areas bear 

 small sharp spinelets. The costae bear spaced, conspicuous, slender 

 spines, usually about 10, of which 3 on each side are much the long- 

 est, and the 4 or 5 median are the shortest, except on the first 2 or 3 

 costae, where the lateral spines are obsolete. The median costal spines 

 of the first 2 or 3 arches are about 2 mm. in length and decrease 

 slightly in length aborad while the lateral 3 spines increase. Of 

 these the outermost is longest and equals the length of about 3.5 con- 

 secutive adambulacral plates. The spines are covered with pedicel- 

 lariae and the papulae extend to the last complete arch, decreasing 

 gradually in number distad. Beyond the eleventh or twelfth costal 

 arch only the 3 lateral spines persist, the median portion of the 

 costa becoming at first rudimentary, these disappearing. 



First 10 adambulacral plates a little higher than long, but length 

 and width about equal as seen directly from below. First 3 subam- 



