208 



if th^re were numerous warts very regularly arranged crosswise. The radial 

 costae number about 5 or 6 in a space of 5 mm. where the intercalation of 

 thinner ones takes place on the dorsal valve. They are somewhat more widely 

 apart from each other. 



In another specimen, also a cast but of the exterior surface of a ventral 

 valve, the radial costae are very narrow, but evenly prominent along the whole 

 of their course. They increase in number anteriorly by means of interpolating 

 new costae between the older ones. The whole surface is traversed by con- 

 centric stria: that are very faint but clearly recognizable. The interspaces are 

 much wider than the costae themselves. This specimen closely resembles that 

 from the Tournaisien of Belgium (PI. XXIV., fig. 7). It is very strange that 

 Frech's attention was not attracted to the di.stinction of the outer and inner 

 surfaces of the valves. 



Dimensions (partially estimated) : — 



Length. Width. Thichness. Hinge-linc. Length of septum, 



ca. 60 mm. ca. 70 mm. 30 mm.+ ca. 60 mm. 20 mm. 



Locality : — East of Tou-tang. Wei-ning-chou, Ta-ting-fu, prov. Kwei- 

 chou. 



Geological Age : — Lower Carboniferous. In the neighbourhood of this 

 locality Prodiictiis cora and Prod. aff. yzmnanensis were found by Prof. K. 

 Yamada. The latter two seem to be Upper Carboniferous or Permo-Carboni- 

 ferous because the Prod, corn of that locality represents the younger type 

 which was described by Diener^^ from the Permian of the Shan States ; while 

 Prod. yuniKDiciisis is a permo-carboniferous''^ species. Thus there seem to be 

 two stages of the Carboniferous Formation developed in that neighbourhood, 

 provided Girty's schedule is strictly followed. 



This is the only species among the fossil brachiopods from China which 

 is strictly lower Carboniferous. It is very interesting that in the vast territoiy 



1) C. DiENER:— Anthracolithic Fossils of the Shan States, p. 19. 1911. 



2) L. V. Loczy: — Wissenschaftl. Ergebn. d. Reise d. Graf. Bela Szechenyi in Ostasien, III., 

 p. 125, pi. VI., figs. I and 2. 1890. 



Width oi the muscular impression. 



25 mm. 



Length of the same. 



17 mm. 



