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Graptolite Net
 is edited and periodically updated by
Piotr Mierzejewski, the Count of Calmont & Countess Maja A. Korwin-Kossakowska
    since 2002
Portal of Graptolites and Pterobranchs sponsored by Artistic Embroidery M.M. plus M.
updated August 8, 2005
LOWER ORDOVICIAN GRAPTOLITE-FAUNAS OF NORTH CHINA
Y.C. SUN
Palaeontologia Sinica, Series B, 1935, XIV, 2, 5-14
I n t r o d u c t i o n

      " Hitherto the only known graptolite-faunas of North China were those of the Pingliang formation of Kansu of
Middle Ordovician age, although a single fragment of graptolite was already reported from the Kaolishan formation
(late Upper Cambrian), Shantung."
       "In 1930 when the Author conducted the National Peking University Field Class in the Kaiping Basin,
Chaokuochuang, were discovered the
Dictyonema faunas in the greenish-gray argillutytes of the Yehli formation.
These faunas are associated with
Lingulella. The following species described in this memoir:"

Dictyonema flabelliforme var. orientale Sun (var. nov.)
Callograptus bulmani Sun (sp. nov.)
Dendrograptus irregularis Sun (sp. nov.)
Dedrograptus grabaui Sun (sp. nov.)
Acantograptus kuoi Sun (sp.nov.)

       "This assemblage is certainly that of the
Dictyonema flabelliforme zone in England and of Tremadocian age.
This zone is, indeed, the oldest Ordovician graptolite zone so far known in China."
       "More recently the Author was again accompanied by the Class of 1936 of the National Peking University and
Drs. Yin and Sze obtained again a large collection of graptolites from the upper horozon of the Yehli formation with
the following species."

"
Dichograptus separatus var. hopeiensis Sun (var. nov.)
Desmograptus yehliensis Sun (sp. nov.)
Loganograptus logani var. kaipingensis Sun (var. nov.)
Didymograptus fearnsidesi Sun (sp. nov.)
Didymograptus nitidus (Hall)
Dendrograptus
cf. grabaui Sun (sp. nov.)"

       "This assemblagae is certainly that of the
Dichograptus zone of England, indicating early Arenigian age."
       "It is clear that zone 1 (the zone of
Dictyonema flabelliforme) and zone 3 (the Dichograptus zone) are definitely
represented in the Kaiping Basin. The intermediate zone of Europe - the
Bryograptus zone (zone 2) has not yet
been found in China. Another interesting fact is that the lower zone of the Yehli formation is characterized by an
abundance of
Dendrograptus and Dictyonema flabelliforme of comparatively high types which are quite unlike
those of the Upper Mississippi Valley, while the upper zone is distinguished by the small and primitive form of
Didymograpotus together with Dichograptus, Loganograptus, Desmograptus and few Dendrograptus."
       "The name "Yehli formation" was first proposed in 1920 by Prof. A.W. Grabau and myself for the Lower
Ordovician, argillaceous limestone in which two species of Suecoceras were obtained by me. The Author revisited
the Kaiping Basin in 1921 in company with Dr. C.C. Young [...]."
       "The discovery of the graptolite-faunas is of great important as these faunas not only confirm the exact age of
the Yehli formation but also indicate a close connection of the seas of Europe and of Asia as well as the close
relationship of the Palaeogeography of these two widely separated regions."
       "Briefly, the Yehli formation id bounded by the overlying Liangchiashan formation and the underlying
Fengshan formation, and is characterized by the abundance of Tremadocian-Arenigian graptolites. It is certainly
equivalent to the Canadian of North America."