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CONTENTS - yi^ 



PART I. GENERAL SUBJECTS ^^^ ^ ^ 



Page 



Chapter i. Etymology, nomenclature 3 



a. Echinus and sea urchin 3 



b. Arbacia punctulata ' 6 



Chapter 2. Historical ° 



a. Greeks and Romans 8 



b. Middle Ages i3 



c. Rondelet to L. Agassiz 14 



d. Modern 16 



e. History of Embryology 1 7 



f. The Pluteus 1 7 



Chapter 3. Fossils 20 



Chapter 4. Uses of sea urchins 22 



a. As food 22 



b. As medicine 24 



c. As food for other animals 24 



d. As cups, lamps, ink 25 



e. In art, on coins and as jewelry 25 



f. As experimental material 26 



Chapter 5. Description 27 



a. Size and shape 27 



b. Color 28 



c. Morphology 3^ 



Chapter 6. Natural history 35 



a. Feeding habits 35 



b. Growth and age 3^ 



c. Regeneration 38 



d. Habitat, burrowing forms and collecting 38 



e. Phototaxis and light reaction 43 



f. Geotropism 44 



g. Locomotion 45 



Chapter 7. Sex and breeding 47 



a. Sex ratio 47 



b. Sex dimorphism (other species) 47 



c. Sex determination in Arbacia punctulata 49 



d. Hermaphroditism 50 



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