i6 



After detailed study of the Cambrian fauna from China, Walcott came 

 to the following important conclusion : 



I. The 7?r<'///r/!/rt; fauna of Shan-tung (Man-to shale), S'lan-s!, Yun-nan, 

 northern India (Spiti), West Australia (Kimberley district) and South 

 Australia, is very distinctive and confined to the Asiatic continent and 

 Australia. It is of Lower Cambrian age, and Obolclla asiatica, fJclcioiiclla 

 mgosa c/iiiu'iisis and RcdlicJiia cJiinoisis are the characteristic forms of the 

 Man-to shale. The climatic condition during the Man-to shale he considered, 

 was arid and severely cold. 



II. The overlying Kiu-lung group of Shan-tung is a succession of I'mc- 

 stoncs and shales ; this indicates a relatively shallow-sea condition and fa\'our- 

 able environment for the life of the sea. The Middle Cambrian fauna of the 

 Kiu-lung group, the Dorypygc fauna, is marked by the absence of the genus 

 Paradoxidcs ; and has in common with the Atlantic Par uioxidcs fauna 

 Dorypygc, Solcnoplciira, Aiioniocarc and some other genera. 



The Middle Cambrian fauna of China is divisible into three subfaunas : 

 a. in the lower subfauna, the species belonging t<> the genera Ptrc/io/^aj-ia^^ 

 Inoiiyin and Agnmhts predominate and a species of Rcdlicliia is found ; b. to 

 the middle, Dorypygc richtJiofeni subfauna, Dorypygc, Dolic/ioinctop/is and 

 Solciioplciira are peculiar ; all these named genera drop out in the succeeding 

 c. upper subfauna, in which the genera Damcsclla, lilackivcldcria and 

 Tcinistioii are found. In Shan-tung the upper part of the Kiu-lung group and 

 the next higher Ku-shan shales contain the said upper subfauna. 



The Upper Cambrian fauna, which is found in Chau-mi-tien limestone 

 of Shan-tung, is characterised by the various species of Iworl/iis, a Cepalopoda, 

 and the trilobite genera Pagodia, Cluiangia, PtycJiaspis, Illaomrus. Thus it 

 contains many genera well represented in North America, as Ptychaspis, 

 Illacujirus, etc. The absence of a true Diccloccp/ialiis in the Chinese fauna 

 is considered by Walcott to be very noteworthy, as the genus is found in 

 association with PtycJiaspis and Il/aciuiriis in the Upper Cambrian fauna of 

 the interior portions of Nor;h America. 



