Plate 5 



Axlmcles tictinnilffiis 



Fig. 1. Segment of aotinostomial ring at interradius, o, o, o, the mouth plates X 10; a 1 , a-, first 

 and second ambulacral plates; ad 1 , first adambulacral plate; i, interradial plate, la, 

 Same, specimen c, X 10. Mouth plates. < >n right the first adambulacral (ad') has 

 been removed to show the process of the oral plate which passes upward to join the 

 interradial ( i) ; a 2 , second ambulacrals. The view is ventro-peripheral. 16. Same,X5. 

 Dorsal view of segment of actinostome; lettering as in 1. 



2. Side view of two skeletal arches of ray, meeting fifteenth and sixteenth adambulacral plates; 



disk to left, specimen n, X10. 2o. Side view of ray at ninth and tenth adambulacral 

 plates, disk to right, '■'.10. 



3. Forty-third and forty-fourth adambulacral plates, the former with characteristically long 



marginal spine, ■ 10. 3a. Armature of fourth and fifth adambulacrals showing position 

 of tube-foot, //, on left; subambulacral spines omitted. '3b. Specimen a, seventh and 

 eighth adambulacrals and furrow spines of opposite side of furrow, X10. a, ambula- 

 cral plate; /), ambulacral pore. 

 166 



