﻿10 BRITISH FOSSIL CRUSTACEA. 



Order— MEROSTOMATA, Dana, 1852. 



I. Sub-Order — Eurypterida, Huxley, 1859. 



1. PterygoUis, Agassiz. 



2. Slimonia, {Page) II. Woodw. 



3. Stylonurus, {Page) H. Woodw. 



4. Eurypterus, Dekay. 

 sub-genus Dolic/iopterus, Hall. 



5. Adelophthalmus, Jordan, 



6. Bunodes, Eichw. 



7. Arthropleura, Jordan. 



8. Hemiaspis, H. Woodw. 



9. Exapinurus, Nieszk. 

 10. Pseudoniscus, Nieszk. 



II. Sub-Order — Xiphosura, Gronovan, 1764. 



1. Belinurus, {Konig) Baily. 



2. Prestwichia, gen. nov. 



3. Limulus, Midler. 



These thirteen genera contain about eighty-three species, which will be found in the 

 accompanying Tables, with their geological position and locality, and also the geographical 

 distribution of each genus as at present ascertained. 



Note. — The divisions given in the following Tables for the Devonian strata must not 

 be supposed to represent their absolute geological succession ; they are only intended to 

 show approximately the English and Scotch equivalents for those rocks which are con- 

 sidered to be of Lower, Middle, or Upper Devonian age. The succession of these beds 

 is even now undergoing revision so as to render their correlation more consistent with 

 those of the Rhine, Belgium, and France. 



