Plate I. 



Fig. 1. Point of an arm of Ophioteresis elegans, seen from the dorsal side. Showing the rudimentary 

 dorsal piates, ^^^h. 



— 2. Point of an arm of Ophioteresis elegans, seen from the ventral side. In the middle line 



are seen the ventral piates. The vertebræ have been omitted on the two proximal joints. ^'■'^Ii. 



— 3. Tentacle scale from one of the distal arm joints of Ophioteresis elegans. ''""h. 



— 4. Side arm-plate oi Ophioteresis elegans (no. 5 from the point), with two hook-shaped spines; 



the rudimentary tentacle scale (t. s.) is seen on the left (aboral) side. The tube-foot has 

 been omitted. 2oo/j_ 



— 5 — 7. Arm spines of Ophioteresis elegans, from the grown joints ; showing distinct traces of 



the primary hook-shape. ""/i. 



— 8. Piece of an arm of Ophioteresis tigris (Lym.) (the type specimen), treated with Eau de 



Javelle, in order to make the piates (the vertebræ) more distinct. ; seen from the dorsal 

 side. The arm spines have been removed. ^^/i. 



— 9. Piece of arm of Ophioteresis tigris (the type specimen), from the ventral side ; treated with 



Eau de Javelle. Showing the ventral piates on the middle of the vertebræ. '^^/i. 



— 10. Piece of an arm of Ophioteresis elegans, from the ventral side; treated with Eau de Javelle. 



The arm spines have been omitted. The ventral piates cannot be distinguished from the 

 vertebra. ^*/i. 



— 11. Ophiothela vincula, ventral side. ^*li. 



— 12. — — dorsal side. ^»lu 



— 13. Ventral plate of Ophiothela vincula. ^^/i. 



