Proceedings. ] 09 



have something to do with respiration. In some Am^ebas, 

 too, a spot may be observed, called the nucleus, but its object 

 is not known. The Amaha has the power of elongating parts 

 of its outer layer into blunt kinds of fingers, and by them it 

 obtains its food. If one of these fingers or pseudopodia (false 

 feet) touches anything eatable, it seems to wrap the object up 

 in its jelly, upon which the body comes up and surrounds it 

 completely, the refuse being subsequently pushed out any- 

 where. I said that the Amceba is almost as simj)ly constituted 

 as anything living could be, but the Foram, which may be 

 described as an Amaba in a shell, seems to be actually 

 simpler, for they never have a contractile vacuole or nucleus, 

 and it seems a most marvellous thing how they could secrete 

 these comphcated shells. Their pseudopodia, instead of bemg 

 blunt fingers as in the Anmba, are fine long threads. Their 

 shells may be of two kinds ; the first, in which the threads 

 are all protruded from one large openmg ; and the second, 

 which is perforated all over like a colander by minute holes, 

 and through these passages the threads are projected; in this 

 latter kind there is a film of protoplasm covering the outside 

 of the shell. The shapes which the Foram. shells assume 

 vary so much that Dr. Carpenter and others have come to 

 the conclusion that it is an impossibility to classify them into 

 genera and species, though they have received distinguishing 

 names. 



Probably the commonest fossil in the Lower Greensand is 

 the large Oyster, of which I have brought a specimen. In 

 the lower part of the formation they occm- in extensive beds, 

 like the oyster-beds which exist at some little distance from 

 the shore at the present day. It shows the scar where the 

 large adductor muscle was attached, by which it closed its 

 valves. It is this muscle in our Natives which gives such 

 trouble to the inexperienced opener of oysters. 



MoUusca or shell-fish lived in large numbers, and some of 

 them were of very high organisation. Among these were the 

 Nautilus Ammonites and Belemnite, all belonging to the class of 

 Cephalopoda, or Mollusca whose organs of locomotion are 

 situated round the head. The first two of these had 



