556 DE. CAKPENTEE'S EESEARCHES ON THE FOKAMINIFEKA. 



merations formed by the reunion of some of those that primarily issue from the pores of 

 the shell. The analogy of other Foraminifera, moreover, renders it very probable that 

 the prolongations of the sarcode-body which reach the surface through the canal-system, 

 will reunite upon it so as to form a continuous investment over the whole ; and that 

 this will be especially the case on the spines, appears to be indicated by the provision 

 there is in the furrowing of the surface, for conveying the prolongations of the sarcode- 

 body to every portion of their exterior. 



206. Thus, then, by interpreting the structural phenomena presented by Calcarina 

 according to the analogy of the facts which have been determined by observation of the 

 living animals of the allied type Eotalia, we seem almost indubitably led to the con- 

 clusion that the canal-system is specially destined for the formation and maintenance of 

 the " supplemental skeleton ; " serving to convey prolongations of the sarcode-body from 

 the segments which occupy the chambers, through the thick layer of solid shell-substance 

 that is secondarily formed around those chambers, and through the prolongations of 

 that layer which constitute the spines; and further, that it maintains a tolerably direct 

 communication between even the innermost chambers of the spire and the external 

 surface, a connexion which would have been cut off by the interposition of the 

 "supplemental skeleton," had not this been provided with some such system of inter- 

 vening canals. 



207. One more fact remains to be noticed, which is of much interest as showing that 

 the growth of the spire and that of the " supplemental skeleton" are to a certain extent 

 independent of each other: I refer to the departure from the regular form that 

 frequently shows itself in the later turns of the spire, which (so to speak) often " run 



Kg. IV. 



D E 



Abnormal specimens of Calcarina. 



wild" in a variety of strange modes, examples of which are so well represented in 

 Fig. IV. A-F, that it is unnecessary to refer to them in other than these general terms. 



