Sand-hoppers, 83. Sauropsida, 154. Scales of fish, 142, 143. Scallop, 107-112. Scorpion, 87, 88. Sex, 10. Sea-Anemone, 54, 59. Sea-Cucumbers, 129, 130. Sea-Fan, 59. Sea-Mats, 119. Sea-Mouse, 72, 159. Sea-Urchins, 23, 33, 122. Shell-fish, 33. Siphonostomata, 102, 106. Skin of Vertebrates, 142. Snail, 98, 114. Snake-Stars, or Brittle-Stars, 128. Species, 30. Spiders, 84. Spiny Ant-eater, 160. Sponges, 33, 44, 63, 68. Sponges, Parasitic, 68. Starfishes, 127. Streptoneura, 29, 100. Symbiosis, 48. T. Teeth, 147, 163. Tentacles (arms or feelers), 54. Ticks, 87. Trichina, 71. Triploblastic (three-layered), 37. Trochophora, 43. Trochosphere larva, 42, 43, 72. Tubicolous (tube-dwelling) Annelids, 72, 74. Tunicata, 33, 44, 135. Turbellaria, 70. Two-layered animals, 34, 36. U. Unicellular animals, 11, 34, 35, 39, 44. Univalve shell-fish, 98. Urochordata, 145. V. Vacuole, contractile, 35. Variation, 24, 26, 28, 32. Varieties, 29. Vermes, 33, 44, 68. Vertebrae (joints of the backbone), 138, 139. Vertebrata, 33, 44, 138. W. Water Animals, 166. Wheel-ball larva, 42, 43. White ants, 93. Wood-lice, 83. Worms, 33, 44, 68. Z. Zooids, 58. Zoologists (_see below_). Zoophyte, 53. Zygobranchiata, 30. Zoologists, names of-- Buffon, 11. Caldwell, 160. Chamisso, 137. Cuvier, 54. Darwin, 24, 76. Dubois, Eugène, 168. Forbes, 17. Gadow, 157. Gosse, P., 54. Grant, Robert, 65. Hæckel, 40, 168. Hertwig, O., 50. Huxley, 37, 78, 136, 154. Kowalevsky, 136. Landsborough, W., 109. Lang, A., 39. Linnaeus, 32, 68. Leuckart, 71. Morgan, Lloyd, 20. Parker, T. J., 32. Roberts, G., 21. Romanes, G. J., 11. Sharp, D., 92. Sollas, 65. Woodward, 109. Transcriber's Note: Obvious typographical errors have been corrected. Original published spelling and hyphenation have been retained as they appear in the original publication, including "debateable" and "cellless". A possible missing "wall" has not been added to the caption for Fig. 5 ("--muscular of intestine"; and reference to "the Italian poet" on Page 138 of the original publication has been preserved. Where figures or tables cut paragraphs, they were moved above or below the paragraph. End of Project Gutenberg's Stories of the Universe: Animal Life, by B. Lindsay