REPORT ON THE OPHIUROIDEA. 



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o 



3 O 

 1 • 



Ophioscolcx glaciaMs, Miill. & Tr., 1 1 °. Two arm bones (w/) and a bit of the 



skin of the disk, close to its margin, 

 to show the very small genital plate 

 (o), genital scale («), and radial 

 shield (/). 

 A mouth angle, with the bases of two 

 arms, from above showing the very 

 large peristomial plate, in three 

 pieces (v,v) and the simple, rounded 

 mouth frames (/). 

 A mouth angle with the bases of two 

 arms, from below, the skin being 

 removed to show the underlying 

 plates, of which the first under arm 

 plate (h) is large and bears two 

 papillae. 



5. Ophiothrix quinquemaculata, Midi. & Tr., f. 



6. 



4. 



i_o 

 l • 



ID 

 1 • 



10 



1 • 



9. Oplriocoma cethiops, Ltk., f 



1 i^- 



Outer face of an arm bone. 

 Inner face of an arm bone. See 

 forward process above umbo ( 1 ). 

 (The figure should be placed 

 vertically.) A mouth angle 

 in profile, exhibiting the large 

 mouth tentacles (r,r), the 

 attachment of a fold of the 

 stomach (St) to the upper 

 point of the jaw ; and the jaw 

 plate bearing tooth papilla? 

 (d') } and shorter teeth (d"). 



11. 

 12. 



13. 



,, f. Outer face of an arm bone. 



,, f. Inner face of an arm bone. 



echinata, Agas., f. Base of an arm, in profile, with the bases of 



spines {p,p), the radial shield (I), genital 

 plate (o), and the base of its scale («). 

 ,, f . Chewing apparatus seen in profile ; hinges 



UYf) attaching this piece to its fellow on 

 the brachial side ; within these are seen 

 the sockets of the two mouth tentacles. 



