292 



RESEARCH IN CHINA. 



On the whole these Ordovician faunas described by Kayser may be con- 

 sidered as indicating essentially the same geologic horizon as those collected 

 bv the more recent expedition, although the relationship is not so close as 

 that between the recent collection and the one from Shen-si described by 

 Martelli. The three localities where this horizon is recognized in northeast- 

 ern Ssi'-ch'uan and southern Shen-si are situated at the angles of a large 

 triangle, each limb of which is from 200 to 300 miles (320 to 480 km.) in 

 length, and it is not improbable that beds belonging to this same general hori- 

 zon have a somewhat wide geographic distribution in central China. 



In correlating the fauna of the Ki-sin-ling limestone collected by the 

 Carnegie Institution of Washington Expedition with the Ordovician faunas 

 of other parts of the world, it is necessary to consider two conspicuous 

 elements, the brachiopods and the trilobites; the remaining portions of the 

 fauna, being unimportant, may be disregarded. 



The brachiopods are represented by nine species, two of which have been 

 identified only generically, and of the remaining seven species three are de- 

 scribed in the present report as new, and one, from southern Shen-si, has been 

 described by Martelli. The previously known species from other parts of the 

 world are Orthis calligramma Dalman, Dalmandla tcstndinaria (Dalman), and 

 Dahnanella subceqiuita (Conrad). The first of these, Orthis calligramma, is not 

 recognized as occurring in North America in Schuchert's " Synopsis of Amer- 

 ican Fossil Brachiopoda," but it is a conspicuous north European species, 

 being recognized in various localities in Great Britain, Sweden, and Russia. 

 In Great Britain Davidson gives the range of the species as through the 

 Llandeilo, Caradoc, Llandovery, and Wenlock formations,' the greater num- 

 ber of specimens he has illustrated being from the Caradoc. The Chinese 

 examples most closely resemble those from Russia illustrated by de Verneuil, 2 

 whose stratigraphic position is given by that author as "dans les couches les 

 plus profondres de la formation silurienne." The range of the species in the 

 Baltic provinces of Russia, as recorded by various more recent authors, seems 

 to be from the upper portion of the Glauconite limestone to the Jewe beds. 

 The second of these species, D. testiidinaria, has a wide geographic distribu- 

 tion and has been recognized in many localities in North America and Europe. 

 The species ranges throughout the middle and upper Ordovician. The third 

 species, D. siibccquata, is a North American form which has not been recorded 

 from Europe, and the Chinese specimens agree in all essential details with 

 North American examples. In North America the species is highly char- 

 acteristic of the lower portion of the middle or Mohawkian division of the 

 Ordovician, being especially abundant in the Black River or in faunas of 

 equivalent age. 



The species of brachiopods described as new in this report, with the one 

 described by Martelli from Shen-si, belong to the genera Triplecia, Plector- 

 this, Clitambonites, and Hemipronites. The genus Triplecia occurs in North 



'Monog. Brit. Sil. Brach., p. 245. 'Geol. Russia and Ural Mts., vol. n, p. 207, plate 13, figs. 7 a-/. 



