70 Dr. F. A. Bather — Alleged Prints of Triassic Echinoderms. 



VII. — Alleged Prints of Echinoderbis in Triassic Reptilipeeous- 



Sandstones. 



By F. A. Bather, M.A., D.Sc, F.G.S. 



IN the Geological Magazine for January, 1901 (n.s., Dec. IV, 

 Vol. VIII, pp. 3, 4), Professor Burckhardt describes certaia 

 markings in the sandstone matrix of specimens of Hyperodapedon 

 and Bhynchosaurus in the British Museum, from Elgin, Shropshire, 

 and Warwickshire (the last, however, not being, as implied by 

 the legend to the figure, represented in the Museum). He 

 believes that these are hollow imprints " left by Echinoderms of 

 a Euryalid shape, having peripheral arms, either simple or forked," 

 but he appeals to specialists to decide to which group of Echinoderms 

 they are due. Since these marks are said to be exceedingly numerous,^ 

 and since Dr. Burckhardt uses them as evidence of contemporaneity,^ 

 I thought it my duty, as the specialist nearest at hand, to examine 

 these statements without delay. 



Any student of Echinoderms would probably gather from Professor 

 Burckhardt's description that the impressions were those of Penta- 

 crinid columnals, with a pentagonal lumen, and with occasional 

 cirri. The outlines drawn by Dr. Burckhardt do not really agre& 

 with that of the disc of a Euryalid ophiuran, nor does the paucity 

 of alleged arm-structures confirm that suggestion. The asserted 

 abundance of the pentagons also favours the idea that they are due 

 to Crinoid columnals, for many sandstones filled with imprints of 

 those structures are known from all parts of the world and all ages, 

 including the Trias. The only difficulty that a reader would find 

 in accepting this conclusion would be, that these immensely 

 numerous and by no means minute appearances have escaped the 

 notice of all the eminent geologists and palaeontologists who have 

 devoted to these sandstones the most anxious and pertinacious' 

 scrutiny. 



Examination of the actual specimens, in which I received the kind 

 help of Dr. A. Smith Woodward, has led to very difiFerent results. 

 In common with those of my colleagues whom Professor Burckhardt 

 endeavoured to convince, I am absolutely unable to distinguish the 

 appearances described and drawn by him. Anyone that looks long, 

 enough at a rough sandstone surface can make out as many patterns 

 as there are faces in the fire. But a scientific question is not to 

 be decided by the vote of a majority, and the fact that we cannot 

 see may only show that our senses are deficient. Fortunately there 

 is other evidence. 



Professor Burckhardt himself adduces the "hollows left by Elgin- 

 reptiles " in favour of his interpretation. But these hollows are all 

 quite smooth and are iron-stained darker than the matrix, in these- 

 respects resembling the hollows left by Echiuoderra fragmetits in 

 many another sandstone. Moreover, the fractured rock surfaces of 

 the British Museum specimens under discussion do show imprint* 

 in places, whether of dermal armour and scales, or abdominal ribs, 

 or perhaps fragments of some other creatures ; and all the marking* 



