BUFFALO SOCIETY OF NATURAL SCIENCES 3 1 



eurypterids, which are recognized in our formations. (Pterygotus 

 and Eurypterus). 



" . . . . Far from finding individuals complete and well 

 preserved, it will prove difficult to add any new facts of importance 

 to those already published on the organization of the species of this 

 type. 



"That advantage is not reserved for us, for the Silurian basin of 

 Bohemia, so favored in all other respects, is relatively poor in fossils 

 of the genus Pterygotus, not only because of their great rarity, but 

 also because of the reduction of the specimens to little fragments. 

 Since almost all of the remains are found in the large horizon of the 

 Cephalopods, that is, in our limestone band e 2, it seems to us that 

 one may attribute the almost total disappearance of these gigantic 

 Crustacea to the voracity of these molluscs, against whom they were 

 forced to maintain the struggle for existence." (13, 556). 



We need not consider seriously this interpretation of thefrag- 

 mental character of the eurypterid remains as they can be interpreted 

 in another manner (see p. 199). 



Semper (261) has recently done some work in the region and has 

 revised and added to Barrande's original species. In ei /3 at Podol 

 Dvorce, near Prague, he has collected a few fragments to which he 

 has given the name Pterygotus barrandei of which there are also some 

 fragments at Dlouha hora, in horizon e2. A few endognathites from 

 the former locality have been described as P. beraunensis Semper, 

 since they come from near Beraun. Some fragments of a swimming 

 foot are also described by Semper from e2, as P. blahai, in a thinly 

 laminated limestone rich in Orthoceras which occurs at Visnovka near 

 Lochhov. Of all the species found in Bohemia the best one is a 

 fragmentary individual showing the head with the first eight somites 

 attached, and a few separate fragments, these constituting the species 

 Eurypterus acrocephalus Semper from horizon ei, at Dvorce. From 

 these various occurrences it is apparent that the eurypterids, though 

 represented by a large number of species in the beds of Wenlock or 

 Niagaran age of Bohemia, are found only rarely and in a most frag- 

 mentary condition, although the large marine fauna occurring in the 

 same horizon is one of the largest and most perfect that is known, 

 forming the basis for Barrande's ponderous work on the Systeme 

 Silurienne in which many volumes are devoted to the description 

 and figuring of the marine fossils, while a very little space suffices 

 for the meagre eurypterid fauna. Barrande notices in a paper on the 



