556 
DE. CAEPENTEE’S EESEAECHES OX THE FOEA^IESTFEEA. 
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 Avhich have been determined by observation of the 
living animals of the allied type Botalia, we seem almost indubitably led to the con- 
clusion that the canal-system is specially destined for the foiTnation 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, th at it maintains a tolerably direct 
communication between even the innermost chambers of the spu'e and the external 
surface, — a connexion which would have been cut off by the interposition of the 
“supplemental skeleton,” had not this been prorided 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 departui’e from the regular form that 
frequently shows itself in the later turns of the spire, which (so to speak) often “ run 
Eig. IV. 
B c 
Abuormal specimeus 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. 
