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THE OCEAN WORLD. 



of this stem are usually very numerous, cylindrical, and present a series 

 of rays striated upon their articulated faces. In Pe?itacri)ius they are 



Fig. 107. — Pentacrinus europseus (Thomijson). 



prismatic and pentagonal; that is, they present five projecting angles, 

 and on their articulated face a star with five branches, or, better still, 



