NO. 1415. CAMBRIAN FA UNAS OF CHINA— WALCOTT. 



Coscinocyatlms cf. cancellatus Born. Microdiscus kochi von Toll. 



S'pirocyathus, species undetermined. Microdiscus, species undeterniineil. 



RlmJidocyatlms sibiricus von Toll. Agnostus schmidti von Toll. 



Pr(jtopharetr(i, species undetermined. f Olenellus, species undetermined. 



HelminthoidicJinites sp. Dorypyge slatskoivskii Schmidt. 



KiUorgina cingidata Bill. Ptychoparia czekanowski von Toll. 



f Obolella chromatica Bill. Ptychoparia meglitzkyi von Toll. 



Hyolithes, species undetermined. f Solenopleura sibirica Schmidt. 



Microdiscus lenaicus von Toll. Bathyuriscus howelli Walcott. 



In the autumn of 1003 the Carnegie Institution of Washington sent 

 an expedition to China under the direction of Mr. Bailey Willis, with 

 Mr. Eliot Blackwelder as assistant in stratigraphic geolog}^ One of 

 the objects of the expedition was to obtain data of the Cambrian forma- 

 tions and contained faunas for tlie purpose of comparison, and cor- 

 relation, if practicable, with the North American sections and faunas. 

 Mr. Willis delegated to Mr. Blackwelder the study of the sections and 

 ver}' largely the collecting of the fossils. It was understood that the 

 collections of Cambrian fossils should be studied by Mr. Walcott and 

 the stratigraphic sections elaborated by Mr. Blackwelder. 



A considerable (Quantity of material was collected and recei\"ed in 

 Washington in the fall of 190-1. The preparation of the specimens 

 for labeling was given to Mr. Henry Dickhaut, with instructions to 

 work them up carefully and secure ever\' species possible from the 

 mass of fragments of trilobites, brachiopods, etc., of which nearly 

 all the specimens of rock are composed. The material when thus 

 prepared was labeled with locality and formation nmnbers and taken 

 in hand b}' Miss Elvira Wood, who separated the species and selected 

 and indicated specimens for illustration. I tirst studied the ])rachiopods 

 in connection with my systematic study of the Cambrian braehiopoda, 

 and published descriptions of 23 species in 1905.'* Mr. Willis and Mr. 

 Blackwelder informed me that they would like, in July, 1905, a list of 

 all the species in the collections in order to use them in the correlation 

 of the various sections and the discussion of the stratigraphic geology. 

 To meet this request, I made a preliminary study of the fauna, and 

 now publish it in advance of the illustrated report, which will not be 

 ready to go to the printer before the spring of 1906. Many drawings 

 have been prepared, but it will require several months to complete 

 them. 



In this preliminary study a number of free cheeks and pygidia of 

 trilobites have been passed over, as the time available before I go to 

 the field is not sufficient for the extended examinations and compari- 

 sons needed for a linal paper. 



The large fauna discovered in the reconnaissance made by Messrs. 

 Willis and Blackwelder is an indication of the richness of the Cam- 

 brian faunas of eastern Asia, and of the great results that may be 



aProc. U. S. Nat. Mus., XXVIII, 1905, pp. 227-337. 



