. GENUS ACICULARIA. 139 



of the impossibility of maintaining the existence of a fundamental distinction between 

 the Monothalamous and the Polythalamous Foraminifera. It was formerly pointed out 

 (1.52) that there are organisms which although actnalljj monothalamous are jmtcntially 

 polythalamous : the growth of the single chamber being unlimited, like that of the animal 

 which forms it ; and nothing being required but the development of septa marking out the 

 whole body into an aggregation of segments (which we shall see to take place in the parallel 

 forms belonging to the arenaceous type), to convert such Monothalamia into Polythalamia. 

 Now in Badijlojxjra and in Acicidaria we have organisms which, though actually polythalamous, 

 are potentially as monothalamous as the Ovulites to which they were likened by D'Orbigny. 

 For although the organism, as a whole, is made up of an aggregation of chambers, yet the 

 absence of any internal communication between these chambers, and the want of any other 

 external connection than that which is established by the more or less complete adhesion 

 of their walls, really place them upon exactly the same footing of mutual relationship as that 

 which might exist among a colony of separate Layence or Orbulince developed by gemmation 

 from a single individual. It seems quite obvious, that, as in Badyhpora (^ 189), the parts 

 of the composite fabric must have been brought into mutual relationship by the continuity 

 of the sarcode-body, which probably extended itself over the exterior of the shell durino- the 

 whole of life, and added new chambers whenever it had the material to construct them. 



204. Geolor/ical Distribution. — It is only, as yet, in the Eocene Tertiaries of France, that 

 this genus has been found. It is not known to exist at the present time. 



