OPIIIOCOMA PUMILA. 



GROUPING OF SPECIES HEREIN DESCRIBED. 



71 



One tentacle-scale, ^ 



Two tentacle-scales, 



O. J 'alcncice. 

 0. pumila. 

 O, Alcxandri. 

 0. Jiiisei. 



. Near base of arm, sometimes two tentacle-scales, 0. cBthiops. 

 ' Arm-spines about C(|ual, O. nigra. 



( 0. er.ltinata. 

 Upper arm-spines longest, I 0. erinaceus. 



V 0. scolopendrina. 

 Lowest arm-spine longest, 0. insularia. 



Six slender arm-spines ; disk and arms lined and ) .-. 



spotted, j 



Disk granulation very fine and close ; spines ) >o i 



regular, ) ^ 



pica. 



Ophiocoraa Valenciae MCll. & Trosch. 



Ophiocoma Valencice MiJLL. & Trosch. Syst. Asterid., p. 102. 

 LIST OF STECIMENS. 



Ophiocoma pumila Lltken. 



ophiocoma pumila LiJTKEX. Vidensk. Meibk'lelser. Jan., 1856. 

 Ophiocoma placentigera LiJTKEX. [Labelled speeimens.] 

 Ophiocoma pumila LOtken. Addit. ad Hist. Oph., p. 146. 



Special Marks. — Commonly five arm-spines ; first or second spine 

 longest. 



Description of a Specimen. — Diameter of disk, IS"""' ; from outer 

 edge of mouth-shield to outer corner of opposite mouth-slit, 5""" ; 

 greatest width of arm without spines, 2.2"""' ; length of arm about 75°"° ; 

 distance from outer edge of mouth-shields to inner point of tooth- 

 papilhx?, to that between outer corners of mouth-slit.^, 2.5 : 2.5. Mouth- 

 papilla) short, stout, longer than broad, much rounded, often nearly egg- 

 shaped, somewhat irregularly disposed ; innermost one more pointed 

 and tooth-like ; about fourteen to each angle of moutli. Tooth-papilhw 



