PASCEOLUS, CYCLOCRINUS, AND NIDULITES. 1 89 



LITERATURE. 



I. Arch.^eocyathin^e. 



1. " Palaeozoic Fossils of Canada," vol. i., 1861-65. Billings. 



2. " The Dawn of Life" (p. 151). Dawson. 1875. 



3. " Second Contribution to the Studies on the Cambrian Faunas of 



North America." 'Bull. U.S. Geol. Survey,' No. 30. 1886. 

 Walcptt. 



4. " Die Yersteinerungen des Cambrischen Schichtensystems der Insel 



Sardinien." 1886. Bornemann. 



5. " On Archaeocyathus, Billings, and on other Genera allied to or associ- 



ated with it, from the Cambrian Strata of North America, Spain, 

 Sardinia, and Scotland." ' Quart. Journ. Geol. Soc.,' vol. xlv. 

 1889. Hinde. 



II. Pasceolus, Nidulites, and Cyclocrinus. 



1. " Palaeozoic Fossils of Canada," vol. i. 1861-65. Billings. (Pasceolus.) 



2. " Nidulites." ' Quart. Journ. Geol. Soc.,' vol. vii., 185 1. Salter. 



3. " Cyclocrinus." ' Lethasa Rossica.' i860. Eichwald. 



4. " Nidulites." ' Monograph of the Silurian Fossils of Girvan.' 1878. 



Nicholson and Etheridge, jun. 



5. " Lethaea Palaeozoica." 1880. Ferd. Roemer. 



6. " On the Structure and Affinities of the Family of the Receptaculitidae." 



'Quart. Journ. Geol. Soc' 1884. Hinde. 



