Chart of the World showing- the Distribution of the Lower Graptolite Faunas 



Legend 



Land areas at tlie begiuniug of the Cliamplaiu (Lower Siluric) era in drab tint; tlieir 



boundaries copied, witli some alterations, from Freeh [1897] 

 ■ Localities of zone with Diotyonema flabelliforme 



• " " Tetragraptus-Phyllogra])tus zones (zones 1 and 2 of Deep kill section) 

 + " " zone with Diplograptus dentatus (zone 3 of Deep kill section) 



* " " Goniograptus thureaui 



