152 



CONNECTICUT GEOL. AND NAT. HIST. SURVEY. 



[Bull. 



Rough-skinned Thyone, 136. 



Sand-dollar, 96, no. 



internal anatomy, 96. 

 Sea-urchins. See Echinoidea. 

 Single-striped Thyone, 135. 

 Slender-armed starfish, 58, 63. 



development, 58. 

 Spatangoidea, 106. 

 Spinulosa, 59. 

 Starfish, abnormalities, 44. 



age at sexual maturity, 42, 48. 



artificial fertilization, 50. 



breeding season, 49. 



damage to oysters and other 

 mollusks, 33, 57- 



effect of mutilation, 47. 



fertilization, 49. 



habits of young, 56. 



losses caused by, 34. 



method of feeding, 30. 



methods of controlling injuries 

 by, 35, 37, 39, 56, 58. 



species of, 58. 



See also Asteroidea. 

 Strongylocentrotus drobachiensis, 

 14, 85, 86, 89, 106, 108. 



description, 109. 



geographical distribution, 198. 



habits, 109. 

 Synapta, 15, 124, 127. 



habits and food, 124, 138, 141. 



regeneration, 127. 

 Synapta inhere ns, 15, 129, 138, 140, 

 142. 



description, 139. 



geographical distribution, 138. 



habits, 124, 138, 141. 

 Synapta roseola, 15, 129, 141. 

 description, 141. 



geographical distribution, 142. 

 habits, 142. 



Thyone, 15, 116. 



alimentary canal, 116. 



body walls, 121. 



calcareous ring, 118. 



cloaca, 118. 



food, 123. 



habits, 122. 



internal anatomy, 116. 



musculature, 121. 



nervous system, 121. 



reproductive organs, 121. 



respiratory tree, 119. 



water-vascular system, 119. 

 Thyone briar eus, 15, 114, 117, 120, 

 129, 133. 



description, 133. 



geographical distribution, 133. 

 Thyone scabra, 15, 114, 122, 129, 



136. 

 description, 137. 

 geographical distribution, 136. 

 Thyone unisetnita, 15, 114, 122, 129, 



135- 

 description, 135. 

 geographical distribution, 135. 

 Tube-feet, ophiuran, 71. 

 starfish, 22. 



Variation in number and arrange- 

 ment of rays, starfish, 43. 



Water-vascular system, holothurian, 

 1 19. 

 ophiuran, 73. 

 sea-urchin, 90. 

 starfish, 26. 



Zygophiurae, 79. 



