BUFFALO SOCIETY OF NATURAL SCIENCES 201 



at different horizons, and continuous widespread faunas are entirely 

 wanting. 



(i) As illustrations of the scattered occurrence of single speci- 

 mens of eurypterids may be mentioned: Strabops thacheri in the Upper 

 Cambric, Echinognathus clevelandi from the Utica, Eurypterus promi- 

 nens from the Clinton, Eurypterus boylei from the Guelph, Eurypterus 

 micro phthalmus from the Manlius, and Eurypterus douvillei from the 

 Rothliegende. 



(2) As an instance of the same species occurring in places many 

 miles apart, Eurypterus remipes may be cited. This species has been 

 found in Waterville, Oneida County, N. Y. in great numbers; at 

 Jerusalem or Wheelock's Hill, Herkimer County; to the northeast 

 (near Cedarville) and west (Paris Hill) of Jerusalem Hill, near 

 Oriskany; at Cayuga Junction, Cayuga County; and possibly at 

 Buffalo. In all of these localities it has been found in the uppermost 

 part of the Bertie, but at Seneca Falls, Seneca County, specimens 

 have been found in the Rondout Waterlime (which may be possibly 

 of the same age as the Bertie). There are several cases of closely 

 related species occurring in localities separated often by great dis- 

 tances. One example that may be cited is that of Eurypterus lacustris, 

 E. remipes and E.fischeri. For a long time the Baltic form (E.fischeri) 

 was identified with E. remipes and it was not until Eichwald pointed 

 out the differences in surface sculpturing and certain other charac- 

 teristics, that the species was made distinct. Clarke and Ruedemann 

 conclude their discussion of the comparion of these two species by 

 saying that, "Altogether, the differences are so small that Schmidt's 

 suggestion that they are but geographical varieties is fully supported" 

 (39, 172). They add, further, that E. remipes and E. lacustris "are 

 more closely related to each other than either of them to E. fischeri, 

 indicating that they had but lately separated. Their differences rest 

 mainly in the shape of the carapace and they are duplicated by those 

 between E. fischeri and E. laticeps, two forms associated in the same 

 [Baltic] rocks" (39, 172). Eurypterus fischeri has been found in Oesel 

 and in Podolia. 



(3) The data on the distribution have brought out clearly the fact 

 that at no geological horizon is there a widespread or continuous 

 eurypterid fauna indicating passageways of migration. Even in the 

 Upper Siluric, which marks the acme in all respects for the euryp- 

 terids, the fauna does not show that universality which would be 

 expected of denizens of the sea or of organisms whose immediate 



