FAUNA OF THE KI-SIN-LING LIMESTONE. 293 
America, although it is apparently an immigrant in our faunas. The Chinese 
species 7. polo, however, is of the typical American form of the genus, being 
more or less remotely related to 7°. extans Emmrich of the Trenton limestone. 
The range of the genus in North American faunas is from the lower Ordo- 
vician or Canadian to the Niagaran division of the Silurian. Plectorthis is 
a widespread genus in the Ordovician faunas of both North America and 
Europe. Clitambonites occurs rarely in the middle Ordovician or Mohawkian 
faunas of North America and more commonly in the European faunas, its 
relationships are European rather than American, and Hemipronites is strictly 
a European genus. Both of these two last genera have their greatest develop- 
ment in the faunas of the Baltic provinces of Russia, where they occur in the 
Glauconite and Vaginatus limestones associated with Orthis calligramma. 
The genus Strophomena, which occurs abundantly in the Chinese fauna, 
although the species has not been identified, is a much more conspicuous 
member of the North American Ordovician faunas than those of Europe, 
although it is not uncommon in Europe. 
Among the trilobites the most conspicuous feature in the Chinese fauna 
is the great variety of Asaphide belonging to the genera Asaphus, Megalaspis, 
and Jsotelus. Another notable faunal character is the presence of the genus 
Ampyx. Although none of the species of these genera of trilobites has been 
certainly identified with previously known forms, the complexion of the whole 
assemblage is strongly suggestive of the same Ordovician faunas of the Baltic 
provinces of Russia that are characterized by the brachiopods Hemzpronites, 
Clitambonites, and Orthts calligramma. ‘The genus Jsotelus is conspicuous in 
the North American faunas, but Asaphus proper and Megalaspis do not occur. 
Among the Chinese species Asaphus blackwelderi and the pygidia compared 
with Asaphus expansus Dalman are of first importance. In Russia Asaphus 
expansus, which is certainly a close ally of these Chinese forms, is particularly 
characteristic of the Glauconite limestone, and it occurs also in Scandinavia 
atasimilar horizon. ‘The species here described as Ampyx chinensis 1s closely 
allied to A.nasutus Dalman, whichoccurs in both the Glauconiteand Vaginatus 
limestones of the Baltic provinces of Russia and in limestones of similar age 
in Scandinavia. Ampyx costatus Boeck, with which one of the Chinese 
species is compared, occurs in the Echinospherites limestone of the Baltic 
provinces, the formation superjacent to the Vaginatus limestone. 
The single form of cephalopod from the Ki-sin-ling limestone has been 
referred to the genus Vaginoceras. In America the described species of this 
genus occur in the Black River limestone. In the Baltic provinces of Russia 
the genus is represented by the Orthoceras vaginatum, whose great abundance 
has given name to one of the Ordovician formations of that region, the Vagin- 
atus limestone, sometimes also called the Orthoceras limestone. 
The above analysis of the Chinese fauna described in this paper shows 
clearly its strong relationship with the north European Ordovician faunas, 
and especially with the fauna of the Glauconite and Vaginoceras limestones 
