52 THE HABITAT OF THE EURYPTERIDA 



Original Name Present Name or Status 



P. acuticaudatus Pohlman Pterygotus buffaloensis (Pohlman) 



P. banksii Salter P. (Erettopterus) banksii Salter 



P. buffaloensis Pohlman P. buffaloensis (Pohlman) 



P. cobbi (P. cummingsi) Semper P. cobbi Hall 



P. comes Barrande P. bohemicus Barrande 



? P. cummingsi Grote and Pitt P. buffaloensis (Pohlman) 



P. cummingsi Grote and Pitt P. cobbi Hall 



P. cyrtochela Barrande Doubtfully identified, no standing 



P. expectatus Barrande Doubtfully identified, no standing 



P. globicaudatus Pohlman Eurypterus pustulosus Hall 



P. globicaudatus Laurie Eurypterus pustulosus Hall 



P. hibernicus Baily Eurypterus hibernicus (Baily) 



P. macrophthalmus ? Pohlman P. buffaloensis (Pohlman) 



P. mediocris Barrande Doubtfully identified, no standing 



P. osborni Hall Pterygotus macrophthalmus Hall 



P. perornatus Salter P. bilobus var. perornatus Woodw. 



P. perornatus var. plicatissimus P. bilobus var. perornatus Woodw. 



P. problematicus Agassiz P. problematicus Salter 



P. problematicus Banks P. gigas Salter 



P. problematicus Strickland and Salter P. problematicus Salter 



P. punctatus Salter Eusarcus punctatus (Salter) 



P. pugio Barrande Doubtfully identified, no standing 



P. quadricaudatus Pohlman Pterygotus buffaloensis (Pohlman) 



P. raniceps (Woodw.) Eusarcus raniceps (Woodw.) 



P. sp. Whiteaves P. atlanticus Clarke and Ruede- 



mann 

 ? P. sp. Sarle P. monroensis Sarle 



CHAPTER II 



A Resume op the Opinions on the Habitat of the Eupypterida 



From 1818 when the first Eurypterus was discovered in America 

 by Dr. S. L. Mitchell until 1900, the order of the Eurypterida was 

 held to be made up of marine organisms. This belief in the marine 

 habitat of the oldest Arthropoda known suddenly became the centre 

 of contention at the beginning of the present century in spite of its 

 long period of security. As soon as geologists considered the possi- 

 bility of origins other than marine for conglomerates, shales and even 

 limestones, there arose discussion as to the nature of the beds in 

 which eurypterids had been found and opinions were perceived to be 

 divergent. It is of interest, then, to take up a systematic review of 

 the literature for the last hundred years and to note what has been 

 the genera] opinion of geologists and palaeontologists about the 



