Contents xv 



CHAPTER XXIX. 

 THE CLASS ELASMOBRANCHII, OR SHARK-LIKE FISHES. 



PAGE 



The Sharks. Characters of Elasmobranchs. Classification of Elasmobranchs. 

 Subclasses of Elasmobranchs. The Selachii. Hasse's Classification of 

 Elasmobranchs. Other Classifications of Elasmobranchs. Primitive 

 Sharks. Order Pleuropterygii. Order Acanthodii. Dean on Acanthodii. 

 Order Ichthyotomi 506 



CHAPTER XXX. 



THE TRUE SHARKS. 



Order Notidani. Family Hexanchidae. Family Chlamydoselachidae. Order 

 Asterospondyli. Suborder Cestraciontes. Family Heterodontidae. Edes- 

 tus and its Allies. Onchus. Family Cochliodontidae. Suborder Galei. 

 Family Scyliorhinidae. The Lamnoid, or Mackerel-sharks. Family Mit- 

 sukurinidae, the Goblin-sharks. Family Alopiidae, or Thresher-sharks. 

 Family Pseudotriakidae. Family Lamnidae. Man-eating Sharks. Family 

 Cetorhinidae, or Basking Sharks. Family Rhineodontidas. The Carcharioid 

 Sharks, or Requins. Family Sphyrnidae, or Hammer-head Sharks. The 

 Order of Tectospondyli. Suborder Cyclospondyli. Family Squalidae. 

 Family Dalatiidae. Family Echinorhinidae. Suborder Rhinae. Family 

 Pristiophoridae, or Saw-sharks. Suborder Batoidei, or Rays. Pristididae, 

 or Sawfishes. Rhinobatidae, or Guitar-fishes. Rajidae, or Skates. Narco- 

 batidae, or Torpedoes. Petalodontidae. Dasyatidae, or Sting-rays. 

 Myliobatidae. Family Psammodontidae. Family Mobulidse 523 



CHAPTER XXXI. 



THE HOLOCEPHALI, OR CHIMERAS. 



The Chimasras. Relationship of Chimaeras. Family Chimaeridae. Rhino- 

 chimaeridae. Extinct Chimaeroids. Ichthyodorulites 561 



CHAPTER XXXII. 

 THE CLASS OSTRACOPHORI. 



Ostracophores. Nature of Ostracophores. Orders of Ostracophores. Order 

 Heterostraci. Order Osteostraci. Order Antiarcha. Order Anaspida. . . . 568 



CHAPTER XXXIII. 



ARTHRODIRES. 



The Arthrodires. Occurrence of Arthrodires. Arthrognathi. Anarthrodira. 

 Stegothalami. Arthrodira. Temnothoraci. Arthrothoraci. Relations of 



