xvi CONTENTS. 



the underlying Cold Water. The Arctic Return Currents. Antarctic 

 Indraught. Vertical Distribution of Temperature in the North Atlantic 

 Basin Page 356 



CHAPTER IX. 



THE DEEP-SEA FAUNA. 



The Protozoa of the Deep Sea. Bathybius. ' Coccoliths/ and ' Cocco- 

 spheres.' The Foraminifera of the Warm and Cold Areas. Deep-sea 

 Sponges. The Hexactinellidae. liossella. Hyalonema. Deep-sea 

 Corals. The Stalked Crinoids. Pentacrinus. Rhizocrinus. Bathy- 

 crinus. The Star-fishes of the Deep Sea. The general Distribution and 

 Relations of Deep-sea Urchins. The Crustacea, the Mollusca, and the 

 Fishes of the l Porcupine ' Expeditions Page 407 



CHAPTER X. 



THE CONTINUITY OF THE CHALK. 



Points of Resemblance between the Atlantic Ooze and the White Chalk. 

 Differences between them. Composition of Chalk. The Doctrine of the 

 Continuity of the Chalk. Objections. Arguments in favour of the 

 View from Physical Geology and Geography. Former Distribution of 

 Sea and Land. Palseontological Evidence. Chalk-flints. Modern 

 Sponges and Ventriculites Corals. Echinoderms. Mollusca. Opinions 

 of Professor Huxley and Mr. Prestwich. The Composition of Sea-water. 

 Presence of Organic Matter. Analysis of the contained Gases. Differ- 

 ences of Specific Gravity. Conclusion Page 467 



APPENDIX A. Summary of the Results of the Examination of Samples of 

 Sea-water taken at the Surface and at various Depths, By William Lant 

 Carpenter, B.A., B.Sc Page 502 



APPENDIX B. Results of the Analyses of Eight Samples of Sea-water 

 collected during the Third Cruise of the ' Porcupine/ By Dr. Frank- 

 land, F.R.S Page 511 



APPENDIX C. Notes on Specimens of the Bottom collected during the First 

 Cruise of the ' Porcupine ' in 1869. By David Forbes, F.R.S. Page 514 



APPENDIX D. Note on the Carbonic Acid contained in Sea-water. By 

 John Young Buchanan, M<A., Chemist to the 'Challenger' Expedition. 



Page 518 



INDEX Page 523 



