104 GREY CHALK MARL. 



Professor Hailstone informs us, that two perfect specimens in the 

 Woodwardian collection, place their vegetable origin beyond aU doubt, 

 and in corroboration of this opinion, mentions, that in the quarry at Cherry 

 Hinton, he had discovered the impression of a branch of some vegetable of 

 the fir tribe, with the hnear leaves surrounding it*. 



On the other hand, Mr. Konig of the British Museum, who did me the 

 favour to examine several Hamsey specimens, remarks, that " these bodies, 

 although possessing a distant resemblance to the juU of the larch, in all 

 probability do not belong to the vegetable kingdom ; for when exposed to 

 the action of muriatic acid, they emit the pecuhar smell, which is so 

 strikingly manifested, in dissolving the madreporitic remains of fetid 

 hmestone ; the putrid exhalation being almost intolerable." 



As these fossils occur in an excellent state of preservation in the marl 

 pits at Hamsey, I had indulged the hope of being able to discover a spe- 

 cimen, that might illustrate their origin, and point out their real nature. 

 But although by the kind assistance of my brother, more than fifty of 

 these bodies have been submitted to my examination, I can add but little 

 to what is already known concerning them. 



The remains in question are of a reddish brown colour, from 0-5 inch to 

 two inches long, of a cyHndrical form, and gently tapering towards the apex, 

 which is obtuse. They are more or less compressed, and have a scaly, cor- 

 rugated surface. Their constituent substance is precisely of the same nature 

 as that of the vertebree, and other bones, found in the chalk formation ; some 

 examples have scales of fishes attached to them. In structure they differ 

 most essentially from any strobilus or cone, for instead of an imbricated sur- 

 face, formed by scales containing seed, and proceeding from one common 

 axis, as in the juli of the larch, their scaly appearance is produced by the 

 undulating margin of the substance of which they are composed; the 

 latter being irregularly coiled in a spiral manner, round an oval cavity or 

 receptacle. This appearance is very obvious in tab. ix. fig. 4, in which the 

 marl is seen projecting through the interstices of the volutions ; at the 



* Geological Transactions, Vol. 3. p. 250. 



