Whe?ice the Shadows? 215 



In classifying the many forms of animal life with which he shares the 

 earth, man has sought names of permanence and international meaning, 

 and has turned to the changeless words of Latin and Greek. He has 

 sought, too, some kind of order in his classification, so he founded two 

 major kingdoms— that of plants and that of animals/ The animal king- 

 dom is divided into great Phyla, or tribes, and, to those who first ex- 

 plore it, this kingdom is a jungle full of familiar creatures with unfamiliar 

 names. The dog becomes Canis familiarise the crow becomes Corvus 

 brachyrhy?2chus; the bullfrog becomes Rana catesbiana. Each species of 

 shark gets a similar double name— the Great White becomes Carcharodon 

 car char ias; the Common Hammerhead, Sphyrna zygaena. 



The first italicized name connotes the genus— a group of species 

 having some fundamental characters in common. The second italicized 

 name is that of the species itself. An animal's scientific name often is 

 based on some obvious physical feature. Carcharodon comes from two 

 Greek words meaning "rough" and "teeth." Sphyrna is derived from 

 the Greek word for "hammer," and zygaena, an ancient word for the 

 Hammerhead, is Greek for "yoke." 



The common names of sharks are handy to use but, when a species 

 of shark is introduced or when the common name might cause confusion, 

 the shark's formal scientific name is used. 



Man and shark share the same phylum— the Ch or data— which en- 

 compasses all vertebrates: fishes, amphibians, reptiles, birds, and mam- 

 mals. Below this level, we all go our own way, including the classifiers 

 who, in attempting to chart man's way through the animal kingdom, 

 have often got lost themselves! Sometimes the sharks are put in a Sub- 

 Class called the Eiiselachii or Flagiostorm; sometimes they are called the 

 Elasmobranchii and upgraded to a Class. It still depends on which book 

 you use. 



Here is a guide to finding the shark in the animal kingdom: 



Phylum: Chordata 



Class: Chondrichthyes (having cartilage instead of bone) 

 Sub-Class: Elasmobranchii 

 Orders: Selachii 

 Batoidei 



And here is how the sharks— as Chondrichthy es— fit into the "fam- 

 ily tree" of the vertebrates: 



1 Currently, three are recognized— animal, plant, and bacterio-virus. There is even 

 the suggestion that animals may be but mobile "plants" derived from algae (seaweeds). 



