46 TOILERS IN THE SEA. 



composed, partly at least, of particles of sand, 

 obtained externally and agglutinated together by a 

 cement supplied by the animal. The fine particles 

 thus collected vary considerably, both in colour and 

 substance. Sometimes the little particles are very 

 uniform and methodically disposed ; at others, they 

 are less uniform, and form only an outer layer im- 

 bedded in a calcareous base. It seems a mystery 

 how such a simple animal as that which inhabits 

 these shells, little more than an atom of living jelly, 

 can deposit one chamber upon another, in the multi- 

 locular shells, with the characteristic markings sculp- 

 tured on the surface, or select and collect the minute 

 particles of sand, and bind them together with 

 admirable uniformity, like a miniature tessulated 

 pavement, on the exterior of the arenaceous shells. 

 Truly "there are more things in heaven and earth," 

 and the deep sea also, " than are dreamt of in your 

 philosophy." 



The simplest form of Foraminiferous shell is that 

 in which the house is restricted to a single chamber. 

 This may be as nearly as possible of a globose form, 

 or oval, or attenuated at one end, so as to be almost 

 pear-shaped, or the neck may be elongated so that it 

 resembles a Florence oil-flask, some being plain, 

 others ribbed or chequered. More complex forms 

 consist of a series of spheres or ovals, adhering in a 

 row, of which each successive chamber diminishes 



