52 



Loc. : — Liu-chia-chao, between Tung-shan-hsieii and Han-ning-hsien^ 

 Wu-chang-fu, prov. Hu-pei (Isiiii coll,) ; in a reddish mottled crinoidal lime- 

 stone. Simply from the nature of its matrix, I prox isionally assign it to 

 Ordovician. 



Cyrtoceratidae. 



Cyrtocers, Goldfuss. 



Cyitoceras (Meloeeras) asiatieum YAtiE sp. nov. 

 PI. XVIII., Fig. 14 ; PI. XXVII., Figs. 7a-b. 



1911. Cyrtoccros {ISIcloccras) cfr. cl/i/>ticinn P'rfxii : Richxhofen's- 

 China vol. V., p. 6, pi. II., figs. 3 a-c. 



Shell very slender : septated part rather strongly and uniformely 

 arcuate, gently enlarging from the posterior to the anterior ; elongate oval in 

 cross section, being somewhat narrower along the external side than 

 along the internal. Siphunclc very narrow, and situated very close 

 to the external side. Septa rather closely set, 2-3 mm. apart. Accord- 

 ing to Fkech, the shell is rather thick and its surface shows only fine 

 striae ; the siphonal wall is very thin and not surrounded by siphonal 

 collar of the .septa. Of the body chamber, only a small portion is 

 known ; it is less arcuate than the septated part. 



Dimensions : — The figured specimen measures r 1 5 mm. along the convex 

 side of the shell (of which the last 26 mm. represents the basal portion of the 

 body chamber), and 80 mm. along the chord. Cross section of the whorl, 

 taken from the middle portion of the shell, 16 mm. long and 13 mm.broad. 



The present specimen, I think, is quite similar to that described 

 by Frech^' under the name C. {M.) cf. cllifticum Lossen ; as the former is 

 almost entirely deprived of the test, it appears to be more slender than the 

 latter. As already pointed out by him, the Chinese form has the septated 



i) C. Lossen: Ueber einige Lituiten. Zeitsch. d. deutsch. geol. Gesell. Bd. XII. i860, 

 p. 27, pi. I., figs. 3 a-b. 



