HIGHER CHORDATES 267 



TAXONOMIC SUMMARY 



Kingdom Animal ia (L. anmmlis, animate) — animals 



Subkingdom Eumetazoa (Gr. eu, true + meta, among + zoon, animal) — eumetazoans 



Phylum Chordata (Gr. chorde, string) — chordates 

 Subphylum Vertebrata (L. vertehratus. backbone) — vertebrates 

 Superclass Pisces (L. piuis, fish) — fishes 

 Class Cyclostomata (Gr. lyklos, circular + stomalos, mouth) — cyclostomes 

 Order Petromyzontoidea (Gr. pelros, stone + myzon, suck + oideos, form or type oQ — 



latnpreys 

 Order Myxinoidea (Gr. myxa, slime + nideos) — hagfishes or slime eels 

 tClass Placodermi (Gr.plakos, flat round plate + derma, skin) — placoderms 

 Class Chondrichthyes (Gr. chondros, cartilage + icklhys, fish) — cartilaginous fishes 

 Order Holocephali (Gr. holos, entire + kephale, head) — chimaeras 

 Order Selachii (Gr. selachos, a cartilaginous fish) — sharks and rays 

 Suborder Batoidea (Gr. batos, a ray + oideos) — rays 

 Suborder Squaloideas (L. i^f/a/i/j, a marine fish + oidetis) — sharks 

 Class Osteichthyes (Gr. osteon, bone + ichlhyes) — bony fishes 

 Subclass Choanichthyes (Gr choana, funnel + ichlhyes) — choanate fishes 

 Order Crossopterygii (Gr. crossoi, a fringe + pteryx, fin) — lobe-finned fishes 

 Order Dipnoi (Gr. di-, two + pnoe, breath) — lungfishes 

 Subclass Actinopterygii (Gr. actis, ray + pteryx) — ray-finned fishes 

 Superorder Chondrostei (Gr. chondros, + osteon, bone) — primitive ray-finned fishes 

 Superorder Holostei (Gr. holos, + osteon) — intermediate ray-finned fishes 

 Superorder Teleostei (Gr. teleos, complete -t- osteon) — modern fishes 

 Superclass Tetrapoda (Gr. tetra, four + podos, foot) — land vertebrates 

 Class Amphibia (Gr. amphi, both or double + bios, life) — amphibians 

 Order Gymnophiona (Gr. gymnos, naked -I- ophwneos, snake-like) — caecilians 

 Order Trachystomata (Gr. trachys, rough + stomatos) — sirens 

 Order Caudata (L. caudatus, having a tail) — salamanders 

 Order Salientia (L. saliens, ]\impine,) — frogs and toads 

 Class Reptilia (L. repere, to creep) — reptiles 

 Order Testudinata (L. lesiudinatus, turtle) — turtles 

 Order Rhynchocephalia (Gr. rhynchos, snout -I- kephale) — tuatara 

 Order Squamata (L. squamatus, scaly) 

 Suborder Sauria (Gr. sauros, lizard) — lizards 

 Suborder Serpentes (L. serpens, serpent) — snakes 

 Order Crocodilia (L. crocodtlius, crocodile) — crocodilians 

 Class Aves (L. avis, bird) — birds 

 Subclass Archaeornithes (Gr. archios, ancient -|- ornithos, bird) — lizard birds 

 Subclass Neornithes (Gr. neos, new + omithos) — true birds 

 Class Mammalia (L. mamma, breast) — mammals 

 Subclass Prototheria (Gr. proto, first + Iher, wild beast) — egg-laying mammals 

 Subclass Theria (Gr. ther) — viviparous mammals 

 Infraclass Metatheria (Gr. meta, after -|- ther) — marsupials 

 Infraclass Eutheria (Gr. eu, true + ther) — placental mammals 



(Figure 16.8), vaguely salamander-like in appearance, These "stem reptiles" gave rise to the great diversity 



were the ancestors of reptiles. Among the earliest of animals that typified the 300-million-year Age of 



groups of reptiles were the so-called "stem reptiles." Reptiles which ended about 70 million years ago. 



