162 



STUDIES IN EVOLUTION 



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Pterygometopus Schmidt. 156 



Ptychaspis Hall. 142 



Ptychometopus Schmidt. 154 



Ptycltoparia Corda. 142 



Ptychopyge Angelin. 146 



Raphiophorus Angelin. 138 



Remopleurides Portlock. 142 



Salteria Walcott. 140 



Salteria W. Thompson. 138 



Sao Barrande. 142 



Sclimidtella Tschernyschew. 148 



Schmidtia Marcou. 142 



Selenopeltis Corda. 151 



Shumardia Billings. 133 



Solenopleura Angelin. 142 



Sphcerexochus Beyrich. 155 



Sphcerocoryphe Angelin. 155 



Sphceropthalmus Angelin. 142 



Staurocephalus Barrande. 155 



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Stygina Salter. 146 



/Symphoria Clarke. 156 



Sympliysurus Goldfuss. 146 



Telephus Barrande. 142 



Terataspis Hall. 150 



Thakops Conrad. 146 



Toxotis Wallerius. 140 



Triarthrella Hall. 142 



Triarthrus Green. 142 



Trimerocephalus McCoy. 156 



Trimerus Green. 154 



Trinudeus Lhwyd. 138 



Triopus Barrande. 133 



Trochurus Beyrich. 150 



Tropidocoryphe Novak. 148 



Uralichas Delgado. 150 



Xiphogomium Corda. 148 



Youngia Lindstrom. 155 



Zacanthoides Walcott. 142 



