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RAYMOND: CORRELATION OF THE ORDOVICIAN STRATA. 219 
Scania, while others are developed in both regions. The table is an 
amplification of one given by Moberg (75). 
Zone of Phacops eucentra and Stauro- 
cephalus clavifrons. 
Trinucleus or | 
Zone of Amypax portlocki. 
Upper Dicellograptus shales 
Zone of Pleurograptus linearis. 
Zone of Calymene dilatata and Dicra- 
nograptus clingant. 
Chasmops or 
Middle Dicellograptus 
shales (with limestone) 
Zone of Nemagraptus gracilis. 
Zone of Climacograptus putillus. 
Zone of Glossograptus hinckst. 
Lower Dicellograptus shales 
Upper Didymograptus shales Zone of Phyllograptus cf. typus. 
Orthoceras limestone 
Zone of Isograptus gibberulus. 
Zone of Phyllograptus angustifolvus. 
Zone of Didymograptus balticus. 
Zone of T etragraptus phyllograptordes. 
Zone of Didymograptus geminus. 
Lower Didymograptus shales | 
Ceratopyge limestone 
Shumardia shale 
Dictyonema shale 
The fauna of the Trinucleus beds has been described by Olin (79), 
who enumerates many species. Of trilobites forty-three species were 
listed, and it is of particular interest to note that twelve of these are 
species common to Sweden and Bohemia. Prominent among such 
species are Cheirurus pectinifer Barrande, Remopleurides radians Barr., 
Calymene incerta Barr., C. pulchra Beyr., Phillipsia parabola Barr., 
“ Asaphus”’ ingens Barr., Trinucleus bucklandi Barr., Ampyx gratus 
_ Barr., A. portlockt Barr., A. tenellus Barr.; and Aeglina rediviva Barr. 
In addition to these common species, the genera Aeria, Staurocephalus, 
and Dionide in themselves suggest the Bohemian fauna. Other 
important species in the fauna are Phacops (Dalmanites) eucentra Ang., 
Agnostus trinodus Salter, and Stygina latifrons Portlock. The im- 
portant graptolites are Dicellograptus complanatus Lapw., and Diplo- 
graptus truncatus Isapw. 
The Chasmops beds contain a rather small fauna,-but although 
there are many limestone bands in the shales, there are fewer trilo- 
bites and more graptolites. Olin lists among others Calymene dilatata 
