420 MESOZOIC TIME — REPTILIAN AGE. 



lina species. Fig. 626 is the Podozamites lanceolatus Emmons, from the same 

 locality. 



Acrogens. — Fig. 628, Clathropteris rectiuscula Hitchcock, from East Hampton, 

 Mass., near the middle of the Sandstone formation : in one specimen there 

 were seventeen such fronds radiating from one stem. Fig. 629, Pecopteris 

 Stuttgariiensis, a fern with the fruit, from the Richmond Coal beds, found also 

 in the Trias of Europe. Fig. 630, Gyclopteris linnsei folia, from Richmond. Other 

 ferns are the Acrostichites oblongus and Laccopteris falcata Emmons, both from 

 North Carolina. Equisetum columnare occurs at Richmond, Va., and in Penn- 

 sylvania. One or two Catamites have been found in North Carolina. 



The vegetation of the beds is decidedly Triassic in character. Pecopteris 

 Stuttgartensis and Pterophyllum longifolium are Upper Triassic in Europe; 

 Laccopteris falcata closely resembles L. germinans, an Upper Triassic spe- 

 cies ; Gyclopteris linnseifolia is near C. pachyrachis, also Upper Triassic ; 

 Clathropteris and Voltzia are Triassic or Jurassic. The prevalence of Cycadeas 

 is decidedly Triassic, and not Permian. Catamites and species of Neuropteris 

 occur in the European Trias as well as in the Permian and Carboniferous. 



2. Animals. 



The Triassic rocks of the Atlantic border have afforded no traces 

 of Radiates, and but few Mollusks. This singular fact is partly- 

 accounted for through another already stated, — that the beds are 

 rarely marine, being in general either fresh-water* or brackish-water 

 deposits. 



Articulates are represented by both Crustaceans and Insects. The 

 Crustacean remains are, with a single exception, Ostracoids ; and 

 some of the species occur in great numbers : two of them are repre- 

 sented in figs. 631, 632. The only fossil Insect observed is the 

 larve (or exuvia of the larve) of a Neuropter (fig. 632 B) related to the 

 genus Ephemera, found by R. Field in the shale at Turner's Falls, on 

 the Connecticut, and described by Hitchcock. It is about three- 

 quarters of an inch long. This tribe of Insects appears to have 

 been numerously represented in the Carboniferous Age (p. 358).* 



* Neuropterous Insects have four similar membranous reticulated wings j as 

 the species of Dragon-fly or Libellula, Termes, Phryganea, Ephemera. 



Orthopters have the outer pair of wings a little coriaceous ; as the Locust, 

 Grasshopper, Cockroach. 



Coleopters have the outer wings wholly coriaceous and neatly meeting along 

 the back ; as the Beetles. 



Hemipters have the outer wings coriaceous for about half their length only, 

 as the Squash-bug, or uniformly thin, as the Gicadse ; the mouth is a sucking 

 beak. 



Lepidopters have large wings covered with minute scales ; as the Butterfly 

 and Moth. 



