AN ACCOUNT OF A LAHOR FOSSIL 5IARINF. WORM. 15 



worm-like '^^mavkings indicating organic origin/' because if the appearances above 

 spoken of are but markings only, how could they shew a circular form on both 

 the upper and lower surfaces? In the case supposed, there would be but the 

 impression on the surface of one lamina, and a cast taken by the lamina 

 superposed, not as in these flags, a circular body. 



An eminent naturalist, to whom a description only was given, thought that 

 the appearances in question might possibly be similar to some noticed by himself 

 on the sea shore, when a strong wind off the land blows the loose sand on 

 the top of the receding wave at ebb tide, enclosing the water within it, 

 which, as it escapes, leaves the sand in the form of long, narrow, sinuous, 

 ridges, depressed along the centre in consequence of the contraction caused by 

 drying, in a manner similar almost to a spinal process; this, however, will not 

 account for the specimens before us, and we mention it more for the purpose 

 of shewing the conjectures that have been made, in order to clear the way for 

 further explanation or full elucidation of the nature ef such fossiliform appear- 

 ances — this paper being more for the purpose of exciting inquiry than of 

 answering the question raised. 



A few further remarks occur to us which may help to throw light upon 

 the subject. The formation in question must have been laid on the shore of 

 a shallow deeply-indented bay — perhaps 



of a salt water lagoon, into which the /f ^--""-x T 



tide had entrance. In the fine mud of F / ^ / ' ^ I j 



this lake have lived and died the • / \ 1 ^ ] \ 



creatures whose motions are impressed fj / I / i\ / ' 



upon the surfticcs, and whose bodies still v-i ^ ^-'' , 



form part of the deposits. They lay in ; . 

 these beds in long folds in shape as in ^ 



the engraving, shewing in some cases the appearance of a tail, but in no 

 instance has any sign of a head been observed, except such a one as would 

 answer to a species of the lamprey. The whole ridge 

 is marked at every quarter of an inch with ribs, which (p^^^^'^^^l'T^ 

 have a very strong resemblance to the ribbing of 

 plants of the equisjtum family. The side view 

 obtained by cracking off the slate, is as in the following figure; in both instances 

 shewing a vermiform appearance. 



A large specimen is deposited in the York '^"^"'^ 

 Museum. 



Bichnond, YorJcsMre, January Wth., I80I. 



