REPORT ON THE ECHINOIDEA. 299 



PLATE XXVII. 



Echinocrepis cuneata, A. Ag. (figs. 1-11), p. 145. 



Fig. 1. Seen from the abactinal side, covered with spines. 

 ,, 2. Same, seen from the actinal side. 



,, 3. Same, seen in profile. 



„ 4. Same, seen facing the anal extremity. 



,, 5. Same, seen facing the anterior extremity. 



,, 6. Interior view, seen from the actinal side, showing the course of the alimentary 



canal. 



„ 7. End view of anterior part of test, denuded. 



„ 8. Tuberculation of interambulacral plates of the median abactinal side of test. 



„ 9. Magnified view of apical system and surrounding j^lates. 



„ 10. Anal system, seen from the actinal side. 



„ 11. Hofiman's organ in Echinocrepis. 



Figs 1-6, natural size ; all others somewhat enlarged. 



PLATE XXVIIL 



Pourtalesia ceratopyga, A. Ag. (figs. 1-12), p. 134. 



Fig. 1. Seen from the abactinal side, covered with spines ; natural size. 



„ 2. Same, seen in profile. 

 ,, 3. Same, seen facing the anterior extremity. 

 ,, 4. Same, seen facing the anal extremity. 



,, 5. Interior view, showing general course of the alimentary canal. 



„ 6. Actinal view of anterior part of test, denuded. 



,, 7. Actinal view of posterior extremity of test. 

 „ 8. Actinal view of a smaller specimen (same as fig. 6). 



,, 9. Abactinal view of anterior part of test of fig. 8. 



„ 10. Interambulacral plates of test to show the regular tuberculation. 



,, 11. Interior view of abactinal part of test. 



„ 12. Abactinal system denuded. 



PLATE XXVIIP. 



Pourtalesia caiinata, A. Ag. (figs. 1-15), p. 133. 

 Fig. 1. Seen from the abactinal side ; natural size. 



