COLLECTION AND SELECTION OF FORAMINIFERA. 447 



FIG. 209. 



Section of Faujasina near its base and parallel to 

 5t: - showin ? , the radiating interseptal canals; 6, 

 their inlernal bifurcations; c, a transverse branch; d 

 tubular wall of the chambers. 



this is especially the case, where, as frequently happens, there is 



an interstitial calcareous skeleton to be nourished (often extend- 



ing itself into outgrowths of 



various forms and sizes), in 



addition to the immediate 



investments of the seg- 



ments; and it becomes ob- 



vious from the far greater 



development of this canal 



system wherever such is the 



case, that this interstitial 



skeleton is chiefly if not 



entirely maintained through 



the instrumentality of the 



"stolons" of sarcode which 



occupy these canals, and 



whose remains may often 



be distinctly traced in the 



dried shell. 1 Now this, the 



highest type of Foramini- 



fei'OUS Structure, is not Only 



r>rP^PTltPrl hv Slioh RTliral 

 Dy Spiral 



forms aS Nummulite, but is 



found also in a genus that is 



conformable, in its concentric plan of growth, to Orbitolite. 

 Hence it is obvious that no arrangement founded, as in that of 

 M. D'Orbigny, upon a character of such secondary importance 

 as the direction of gemmation, is likely to be in accordance with 

 physiological features which a perfect knowledge of the animal 

 might be expected to afford; and as these can be partly judged 

 of from the structure of the shell, it seems obvious that this 

 ought to be made the first consideration. To carry out a classi- 

 fication on such a basis, however, will involve a large amount of 

 patient investigation. 2 



292. Many of the Foraminifera attach themselves in the living 

 state to Sea-weeds, Zoophytes, &c. ; and they should, therefore, 

 be carefully looked for on such bodies, especially when it is de- 

 sired to observe their internal organization and their habits of 

 life. They are often to be collected in much larger numbers, 

 however, from the sand or mud dredged up from the sea-bottom, 

 or even from that taken from between the tide marks. In a 

 paper containing some valuable hints on this subject, 3 Mr. Legg 



1 The Author has been enabled to make out this curious point completely, in the 

 Calcarina, a little body resembling a spur-rowel. For he has obtained ample evidence 

 that the spire with its regularly added segments, and interstitial skeleton extending itself 

 into radiating spines, may grow quite independently of one another. The proof will be 

 submitted in future Memoirs to the Royal Society. 



a To this labor, the Author has been for some years devoting a portion of his very 

 limited leisure, in conjunction with his friend Prof. Williamson, of Manchester ; and the 

 results of their united labors will appear at the earliest practicable period, in the Ray 

 Society's publications. 



3 " Transactions of the Microscopical Society," 2d Series, vol. ii, p. 19. 



