2l8 



1909. Rliynclionella plcurodon Sommer : — Die Fauna des Culms von 

 Konig-sberg bei Giessen. Neues Jahrb, Beil.-Bd., XXVIII., p. 

 630. pi. XXIX., fig. II. 



Several specimens of this species were collected by Mr. IsHii in the 

 province of Hu-pei, together with Spirifer bisulcatiis and Atliyris royssii. 

 In this fauna the la.st species is the most predominant, while RJiym Jionclla 

 plcurodo)i is the rarest, at lest in this collection. Moreover, only a very few 

 are well preserved, so that the characteristics of the species are revealed in 

 such examples alone. One thing that must be remembered is the fact that 

 tke Chinese specimens are on the whole remarkably, smaller than those 

 known from various other parts of the world. In all essential points, how- 

 ever, the fossils at the writer's hand are really nothing but Rhyiichoiclla 

 f!i-urodon. Although in the dimensions of the specimens the Chinese fossils 

 differ to some extent from the figures of Phillips, they are coincident 

 morphologically. The same is the case with the figures in the pictures by 

 the other authors whose names are given above. 



The palaeontologist whose circumscription of the species is the most 

 comprehensive is no doubt Davidson. This is seen at once if his monograph 

 is read through or his figures are examined. Rhynchonclla inantiic, Sow., 

 Rhyiichoiu'lla I'cntilabriiiii, Puill., Rhynchonclla davrcitxiann Dk Koninck 

 and Rliyiuh triplex M'COY were by him united to this .species. Thus this 

 naturalist stands as the opposite extreme to the one represented by De 

 Koninck. The present writer is not disposed to follow either of the two in 

 circumscribing the species. For instance it seems better to tlie writer that 

 Rhynchonclla vmntice as represented by the figures of Davidson, should be 

 retained as an independent species different from RhyncJionclla plcnrodoti. 



Also in this paper the writer is inclined to abandon the species RhyncJio- 

 nclla Icvta De Koninck which was proposed as a new species by the author. 

 Judging from what is said in the description as well as from the pictures, the 

 latter " species "' cannot differ much from the present species, although there 

 may be apparent differences between the two forms. De Koninck confesses 

 that the separation of these two forms as independent was carried out after 

 long hesitation. According to him they differ in dimensions, in description, 



