Fossil Scorpions 125 



A REVIEW OF THE PRESENT KNOWLEDGE OF FOSSIL 

 SCORPIONS WITH THE DESCRIPTION OF A NEW 

 SPECIES FROM THE POTTSVILLE FORMA- 

 TION OF CLAY COUNTY, INDIANA/ 



By John Irwin Moore, Owensville. 



The following paper is a condensed review of the literature on fossil 

 scorpions with the description of a new species from the Pottsville forma- 

 tion of Clay County, Indiana. 



Interest in Fossil Scorpions. Wide interest in fossil scorpions was 

 first aroused by the discovery of a specimen in the Silurian rocks of 

 Sweden which was first made known to the Swedish Academy of 

 Sciences, on November 12, 1884. The fact that this "apparently car- 

 ried the history of air-breathing or land animals much further back in 

 geological time than had hitherto been known"- was enough in itself to 

 attract wide interest. A published statement of the Swedish find first 

 appeared in Comptes Rendu of the French Academy, Dec. 1, 1884. This 

 was closely followed by an announcement of the discovery of a specimen 

 in the Silurian rocks of Scotland, published in the Glasgow Herald, 

 Dec. 19, 1884. Almost a year later (Oct. 10, 1885) a similar find was 

 announced from the Water-Lime beds of New York (Silurian). This 

 almost simultaneous discovery of rare and peculiar fossils caused ac- 

 counts of them to be published in many scientific and popular journals. 



Their Bearing on Geological History. At present fossil remains of 

 scorpions have been described from the Silurian and Carboniferous, and 

 from amber deposits of Oligocene Age. According to Fritsch' the order 

 Scorpionida attained its acme during the Carboniferous and subsequently 

 declined. 



As stated above the Silurian scorpions constitute the earliest sug- 

 gestion of land or air-breathing animals, but Whitfield, concludes that 

 they could not have been air-breathers but were wholly aquatic and that 

 their descendants acquired the terrestrial habit in subsequent genera- 

 tions. Pocock has suggested that the supposed mesosomatic "sternites" 

 of Palaeaphonus are really broadly laminate gill-bearing appendages, 

 as they have been shown to be in Eurypterus\ Similar appendages 

 occur in the Carboniferous Genus Eobuthus, and it is inferred that 

 respiratory lamellae lay beneath them as they do in Limilusl Many 

 writers have expressed the belief in the origin of the scorpions from the 

 eurypterids and this has been used in the development of a theory for 



' To Professor Stuart Weller I wish to express my thanks for many valuable sug- 

 gestions and for his encouragement in attempting the study and description of the 

 specimen. From my brother Prentiss D. Moore I received much assistance in the prep- 

 aration of the photosraphs. Greatest thanks are due Arch AddinKton of Indiana 

 University, who saved the specimen for description. 



- R. P. Whitfield — On a Fossil Scorpion from the Silurian Rocks of North Amer- 

 ica. Bull. Amer. Mus. Nat. Hist., Vol. I. 



'■ Zittel— Text Book of Paleontology. 



' Clarke and Rucdeman — New York Geol. Sur. 



= Zittel— Text Book of Paleontology, p. 788. 



"Proc. 38th Meeting. 1922 (1923)." 



