PLATE XIV. 



I'll 1 N('S( UlsMA < AKYOrilYI.I.ATVM, (If Kotl., sp., 0.277. 



Page 

 Pig. 1. Interradial view of a specimen with the ambulacra removed, exhibiting the form 



of the radial and basal plates, and the position of the hydrospire-slits. Carbo- 

 niferous Limestone, Belgium. x3 1'i 



Fig. 2. A radial sinus with the side plates removed from the lancet-plate, exposing the 



hydrospires on each side. x4 93 



Fig. 3. A radial sinus with the lancet-plate and side plates//; situ. The distal extremities 



of the hydrospire-slits are visible at the sides of the ambulacrum. x 1 . . 57 



Fig. 4. An interradial view of a complete calyx. x4 89 



Pii.exosciiisma Archiaci, E. ty C, p. 27 I. 

 Fig. 5. Summit view of a specimen which has lost nearly all its side plates, so that the 



hydrospire-slits are fully visible. Lower Devonian, Asturias. x 4 ... 80 



Fig. 6. A radial sinus with the ends of the lancet-plates visible above and below, and its 



middle portion covered by the side plates ; one or two hydrospire-slits are visible 



at their sides. x 8 62 



Fig. 7. A radial sinus, with the lancet-plate exposed by the removal of the side plates. 



Six hydrospire-slits are visible on each side. x 8 89 



Phjenoschisma Vebnbtjili, E. § C, p. 273. 

 Fig. 8. Interradial view showing the interradial processes, hydrospire-slits, and some 



remains of the ornament. Lower Devonian, Asturias. x2 24 



Fig. 9. A radial sinus with the narrow ambulacrum intact, and the radio-deltoid sutures 



crossing the hydrospire-slits on the sides of the sinus. x4 (VI 



Ph.enosciiisma acutum, G. B. Sby., sp., p. 27C>. 



Fig. 10. Interradial view, showing the exposed lancet-plates of two ambulacra, and the 



hydrospire-slits at their sides. Carboniferous Limestone, Lancashire. x 3 . 24 



Fig. 11. Summit view of the same specimen. Two of the ambulacra are almost intact, but 

 in two other sinuses only the lancet-plates remain, and in the fifth the whole of 

 the ambulacral plates have been removed. x G 8'J 



Fig. 12. A radial sinus as exposed by the removal of all the ambulacral structures except 

 the tip of the lancet-plate. The visceral cavity is visible in the median line and 

 the hydrospire-slits on its sides. x 8 44 



Pentremitidea Paillettei, de Verneuil, sp., p. 172. 

 Fig. 13. Interradial view, showing the general features of the calyx. Lower Devonian, 



Asturias. x 2 21 



