128. Young Cuvieria 99 129. Cuvieria somewhat older than Fig. 128 99 130. PENTACTA FRONDOSA 100 131. TOXOPNEUSTES DROBACHIENSIS 102 132. Portion of shell of Fig. 131 without spines (Agassiz) 103 133. Sea-urchin shell without spines (Agassiz) 103 134. Sea-urchin from the mouth side (Agassiz) 104 135. Magnified spine 104 136. Transverse section of spine 105 137. Pedicellaria of Sea-urchin 105 138. Teeth of Sea-urchin 106 139. ECHINARACHNIUS PARMA 107 140. Transverse section of Echinarachnius (Agassiz) 108 141. Ray of Star-fish, seen from mouth side (Agassiz) 109 142. ASTRACANTHION BERYLINUS 110 143. Single spine of Star-fish 111 144. Limestone network of back of Star-fish 111 145. Madreporic body of Star-fish 111 146. CRIBRELLA OCULATA 112 147. CTENODISCUS CRISPATUS 114 148. OPHIOPHOLIS BELLIS 115 149. Arm of Fig. 148, from the mouth side (Agassiz) 116 150. Tentacle of Ophiopolis 116 151. ASTROPHYTON AGASSIZII 118 152. Pentacrinus 121 153. ALECTO MERIDIONALIS 122 154. Young Comatulæ 122 155, 156, 157. Egg of Star-fish in different stages of development 124 158. Larva just hatched from egg 125 159-164. Successive stages of development of Larva 125 165. Larva in which arms are developing 126 166. Adult Star-fish Larva (BRACHIOLARIA) 127 167. Fig. 166 seen in profile 128 168-170. Young Star-fish (Astracanthion) in different stages of development 129 171. Lower side of ray of young Star-fish 130 172. Very young Star-fish seen in profile 130 173-175. Larvæ of Sea-urchin (Toxopneustes) in different stages of development 130, 131 176. Adult Larva of Sea-urchin 132 177. Fig. 176 seen endways 133