1873.] SHAltr — 30LITE3 OP XOIiTaAiMPrOXJHIPvE. 301 



determination was due. It had, moreover, been attained under 

 very adverse circumstances ; for at the time when the survey of the 

 district had been undertaken, the Lincolnshire Limestone had not 

 been recognized ; and even Prof. Morris had at first failed to see 

 that this bed intervened between the Northampton Sand and the 

 Great Oolite. It was mainly due to the extensive collection formed 

 by Mr. Sharp that the key to the existence of this important bed and 

 to the geological history of the whole district during the Mesozoic 

 period was discovered. The mapping of the country was not to bo 

 effected by studying merely its lithological characters, but was 

 mainly dependent on a knowledge of the pakeontological features of 

 each of the successive beds. Mr. Etheridgc pointed out the close 

 correspondence between the position of the Northampton beds and 

 those of Yorkshire, with the exception of the absence of the Great 

 Oolite in the latter area. Though the Stoncsfield slates and the 

 Collyweston beds were so similar in lithological character that even 

 the most experienced might take the one for the other ; yet, when 

 the organic contents came to be examined, the difference became 

 evident ; and in Mr. Sharp's paper stratigraphical evidence had 

 been brought to corroborate the palseontological, and to show con- 

 clusively the difference in the horizon of the two beds. 



Mr. Judd could not overestimate the value of Mr. Sharp's labours, 

 extended, as they had been, over nearly a whole lifetime. They 

 afforded another instance -of the great value of local inquiries in 

 geology. It was becoming more and more evident that the sequence 

 of beds which held good for one place required some modification in 

 another, and that in each case there was a more or less distinct local 

 series — showing that in no one locality was the sequence absolutely 

 perfect, as indeed had been already pointed out by Mr. Darwin. 



Mr. Charleswortu remarked on a specimen of the teeth of the 

 genus Lepiclotus exhibited, consisting of cylindrical columns sur- 

 mounted by a conical crown, which struck him os one of unusual 

 interest in the magnificent collection displayed. He commented on 

 the value of such local collections for paloeontological purposes, and 

 on the necessity of their being formed if the progress of geology was 

 to be furthered. 



Prof. Duncan also was highly impressed with the value of Mr. 

 Sharp's collection. He remarked on two specimens of Madrepo- 

 raria, one of which, Thamnastrcea concinna, presented a series of 

 ridges significant of intermittent growth. The other form presented 

 a strange relic of palaeozoic coral forms, being intersected by tabula? 

 like those of ancient times. It afforded an instance of a tabulate 

 Actinozoon, in opposition to the opinion of Agassiz that the Tabulata 

 belonged to the Hydrozoa. Loth species grew on narrow bases ; and 

 though not reef-corals, were forms such as were to be found in the 

 neighbourhood of reefs. Taken in conjunction with the Saurian 

 remains, he thought they were symptomatic of shallow sea con- 

 ditions, such as those existing between the continent of America 

 and the West-Indian Islands. 



Mr. H. Woodward contrasted the collections formerly exhibited 



