7 
Culmination and Decline of Reptiles, Molluscs and Gym- 
no sperms. 
Period of Zoantharia Aporosa (foliaceous corals) ; Zoan- 
tharia Perforata (corals with perforated walls). 
VI. TRIASSIC AGE. 
Tria9 : 19, Bunter Sandstein \Gonchylien in part] ; 20, Muschel- 
kalk [ Gonchylien in part] ; 21, Keuper [Saliferien\. 
First appearance of Mammals ; Turtles ? ; Geratites , Ammonites , 
Pycnocrinidae [shallow cupped Crinoids]. 
Disappearance of Orthoceras , Goniatites ; Heterocercal Gan¬ 
oids. 
Reign of Saurian and Labyrinthodont Reptiles ; Geratites; 
Cycads. 
Period of Dromatherium, Microlestes [Insectivorous Marsupials, 
—the last European] ; Butiodon , Glepsysaurus , Gentemodon, Bathy- 
gnathus [Saurian Reptiles] ; Nothosaurus [a marine Saurian]; La- 
byrinthodon [allied to the frog and crocodile] ; Ganoids, including 
some with homocercal [equally lobed] tails ; Insects ; Nautiloceras , 
Orthoceras [in Europe], Melia, Ammonites , Gonchorhynchus, Geratites 
Tetrabranchs] ; numerous Lamellibranchs ; Spirifer , Terebrat- 
ula*. 
The footprints in the Connecticut river sandstones are regarded as 
Triassico-jurassic. 
VII. JURASSIC AGE. 
Eirst appearance of Dipterous and Hymenopterous In¬ 
sects (flies and bees) ; Squalodonts. 
Disappearance of vertebrate-tailed (heterocercal) Ganoids ; 
Labyrinthodonts ; Spiriferidae ; Strophomenidae. 
Reign of Reptiles ; Hybodonts ; Ammonitidie ; Belem- 
nitidae; Free Crinoids; Decapod and Isopod (equal-footed) 
Crustaceans. 
Period of Pentacrinus, Apiocrinus ; Corals; Star-Fishes; 
Echinoids ; Terebratula *, Bhynchonella * ; Ostreidce ; Am¬ 
monites , Belemnites / Insecteans ; Crustaceans; Worms; 
Ganoid Selachians; Enaliosaurs; Lacertians; Croco- 
dilians ; Deinosaurs (the highest [reptiles) ; Pterosaurs 
(flying reptiles) ; Turtles. Fishes proper (Teliosts) are 
still wanting. 
22 . Eias represented by Sinemurien, Liasien and Toarden. 
First appearance of Pterodactyls ; Lepidoids [mostly obtusely- 
toothed Ganoids] ; Sturgeons ; Chlvleroids [an order of Sharks] ; 
Belemnites; Thecidea [Brach,] ; Planorbis% Paludina *, Melania *! 
Disappearance of Spirifer, Leptcena. 
Reign of Ichthyosaurus [12 species]; Plesiosaurus [12 species] ; Hy¬ 
bodonts [Sharks with conical, striated teeth]. 
