103 PROCEEDINGS OF THE PALEOXTOLOGICAL SOCIETY 



restorations of fossil mammals. As the young of many mammals are striped 

 or spotted, becoming solidly colored later in life, we may, perhaps, infer that 

 the earlier forms in these groups, geologically speaking, were, on the principle 

 of recapitulation, striped or spotted. 



The next paper was read by the author from manuscript and illus- 

 trated with photographs; 20 minutes. 



PALEOZOIC ARACHNIDA — SCORPIONS AND SPIDERS 

 BY ALEXANDER PETRUNKEVITCH * 



(Abstract) 



One hundred and one specimens of Paleozoic Arachnida, mainly from Mazon 

 Creek, 111., were studied and found to belong to forty-two species distributed 

 over twenty-five genera, of which twenty-four species and eleven genera are 

 new to science. A representative of the order Solifugre. heretofore not known 

 from the Paleozoic, has been found in Proiosolpuga carbonaria. A new order, 

 Kustarachna?, had to be established for the three species of the genus Kusta- 

 rachne. All forms studied show the high development which the Arachnida 

 had attained already at that period and suggest the probability of polyphyletic 

 origin. A comparison with the European Carboniferous fauna shows that the 

 American forms, while closely related, are distinct from the European species. 

 Moreover, they are more related to the recent tropical fauna than to the fauna 

 of the moderate zone. 



Before the adjournment of the morning session, which occurred at 

 12.30 p. m., Professor Schuchert announced the gift to the Society by 

 members John M. Clarke and Eudolph Euedemann of their monograph 

 on the Eurypterida in two volumes, which had just come from the press. 

 The volumes were exhibited and placed for more detailed examination 

 in the adjoining exhibition-room. 



PRESIDENTIAL ADDRESS 



At 2 p. m. the members met for the afternoon session, with the ad- 

 dress of the retiring President, Prof. William B. Scott, first on the 

 program. Professor Scott chose for his subject 



THE PERMANENCY OF THE CONTINENTS AND OCEANS 



Following the presidential address a paper by Professor Loomis, trans- 

 ferred from the program of the Geological Society of America, was 

 presented by the author without manuscript and illustrated by charts ; 

 20 minutes. Discussed by W. B. Scott and AT. J. Sinclair. 



1 Introduced by Charles Schuchert. 



