PALEOZOIC TIME — DEVONIAN. 



615 



and besides these, there are the first of true Shrimps, or Macrural Decapod 



958. 



955-958. 



957. 



PoETAGE. — Fig. 955, Mesothyra Oceani ; 956, Dipterocaris penna Dasdali ; 95V, D. Procne ; 958, Palaeopalaemon 

 Newberryi. Fig. 955, Hall ; 956, 957, J. M. Clarke ; 958, Whitfield. 



Crustaceans, Palceopalcemon Newberryi of Whitfield (Fig. 958) 

 Phyllopod genus Echinocaris of the same author 

 there are a number of species ; and the related Me- 

 sothyra Oceani of Hall (Fig. 955) had a length and 

 breadth of more than 10 and 5 inches. Figs. 956 

 and 957 represent carapaces of two other Phyllo- 

 pods. The specimen of PalcEopalmmon was found in 

 Ohio, in the lower part of the Ohio shale. 



6. Limuloids. — The lower beds of the Portage 

 and Upper Chemung have afforded species of Euryp- 

 terus. Also a few abdominal segments of great size, 

 ■which have been made the basis of the species Stylo- 

 nurus Wrightianus, supposed to have been two feet 

 long. 



Of Catskill Eurypterids, one gigantic species, Sty- 

 lonurus excelsior H., has been described from imper- 

 fect specimens found in the Catskill beds of Delaware 

 County, N.Y., and Wyoming County, Pa. The cara- 



Under the 



Chemung. — Fig. 959, Protolim- 

 ulus Eriensis, ventral side. 

 H. 8. Williams. 



