448 
H. BURY. 
EXPLANATION OF PLATES XXXVII, XXXVIII, 
& XXXIX, 
Illustrating Mr. H. Bury’s paper on “ Studies in the Embry- 
ology of the Echinoderms.” 
Reference Letters. 
Ant. Anterior. Post. Posterior. Dors. Dorsal. Vent. Ventral. R. 
Plight. L. Left. 
Fig. 1. — Dorsal view of a young Ophiurid Pluteus, showing the 
arrangement of the enteroccels and the origin of the hydroccel. x 300. 
Fig. 2. — Diagrammatic view of an Ophiurid Pluteus, from the left 
side. 
Fig. 3. — Part of an Ophiurid Pluteus, dorsal view, x 300. 
Fig. 4. — Dorsal view of an Ophiurid Pluteus, just before metamor- 
phosis. X 180. 
Fig. 5. — Dorsal view of an Ophiurid Pluteus, undergoing metamor- 
phosis. The terminal plates are really far more complicated in their structure 
than is here represented. X 300. 
Fig. 6. — Young Ophiurid still retaining some of the arms of the Pluteus. 
X 300. 
Fig. 7. — Diagrammatic view of the left side of an Echinid Pluteus. 
X 180. 
Fig. 8. — Dorsal view of an Echinid Pluteus, showing the arrangement 
of the enterocoels and the origin of the hydroccel. X 180. 
Fig. 9. — Part of a Pluteus of Echinus microtuberculatus, seen from 
the dorsal side. X 300. 
Fig. 10. — Pluteus of Echinus microtuberculatus, seen from the right 
side, x 180. 
Fig. 11. — Young Echinus microtuberculatus, a few hours after 
metamorphosis from the Pluteus. The calcareous plates at the bases of the 
marginal spines are omitted. X 180. 
Fig. 12. — Plates at the aboral pole of a much older specimen of Echinus 
microtuberculatus (diam. 75 mm.), x 75. 
Fig. 13. — Diagrammatic view of the left side of the same larva. X 100. 
Fig. 14. — Dorsal view of a Bipinnaria. x 100. 
