Miscellajieoua. 107 



the hind lobe of a Chelonian plastron from tlie Wealden, which waa 

 remarkable as showing a median row of epidermal shields. The 

 name of Archceochelys valdensis was proposed for the form so repre- 

 sented. The new generic term llyJaochdys was also proposed for 

 the Purbeck Chelonian described by Sir E. Owen as Phtirostcnuun 

 latiscidattoii, and was also taken to include some other forms from 

 the Wealden. 



The second section of the paper treated of the affinities of Plenro- 

 sternum. It was concluded that Z>/f/e/-y7mjH, Cope (as represented by 

 the so-called PJatcmys BuUocl-i), is identical with Fleurostemum, of 

 which there appears to bo only one Purbeck species. Evidence was 

 brought forward to show that in the adult of Fleurostemum the 

 pubis had a facet for articulation with the xiphiplastral ; and it was 

 proposed to refer this genus, together with Flatychelys and Baena, 

 to a new section termed " Amphichelydia," which was regarded as 

 allied both to the true Cryptodira and to the Pleurodira. 



MISCELLANEOUS. 



Triassic Fish-scales from Siberia. By A. Smith Woodwaed. 



So little is known of the palaeontology of Siberian formations that 

 a recent memoir by Dr. J. V. Eohon * upon some fragmentary 

 remains of fossil fishes from the Upper Yenisei is of considerable 

 interest and importance. Even detached scales and bone-fragments 

 are worthy of discussion when obtained from such a source ; and 

 among other fossils the author describes some unsatisfactory speci- 

 mens of this character from an undetermined horizon near the village 

 of Kubekowa. These fossils, however, do not appear to have been 

 sufficiently compared with known forms elsewhere. The scales 

 named Falceotiiscvs sibiricus {loc. cit. p. 12, figs. 22, 28) are so closely 

 similar to those of the Lepidotoid Ganoid Colobodus f that they may 

 be assigned with much probability to this genus ; another fragment 

 (loc. cit. hg. 21) is sculptured like some of the head-bones of Colo- 

 bodus i ; and the associated ring-vertebrae (loc. cit. tigs. 23, 29) may 

 well pertain to the same fish, whereas they indicate a higher stage 

 of development of the axial skeleton than has hitherto been observed 

 in any of the Paheoniscidae. Colobodus has only been recorded as 

 yet from the European Muschelkalk and Lettenkohle, in which it 

 is widely distributed ; and the undetermined horizon of C. sibiricus 

 may thus be provisionally regarded as Triassic. 



* J. V. Rohon, " Ueber fossile Fische vom oberen Jenissei," M6m. Acad. 

 Imp. Sci. St.-Petersboarg, [7] vol. xxxvi. no. 13 (1889). 



t Cf. especiallv W. Dames, Palfeont. Abhandl. vol. iv. (1888), pi, xvi a. 

 figs. 6-8. 



X Cf. W. Dames, tbid. pi, xiv. fig. 1, 



