; 
340 THE MEDALS OF CREATION. Cuap. X. 
a body, or vital mass, of a gelatinous consistence, Which is 
either entire and round, or divided into segments, placed 
either on a simple or alternate line, or coiled in a spiral, or 
involuted round an axis. This body is covered with an 
envelope or shell, which is generally testaceous, rarely carti- 
laginous, is modelled on the segments, and follows all the 
modifications of form and contour of the body. From the 
extremity of the last segment there issue sometimes from 
one, sometimes from several openings of the shell, or through 
the numerous pores or foramina, very elongated, slender, 
contractile, colourless, filaments, more or less divided and 
ramified, serving for prehension, and capable of entirely 
investing the shell. 
The body varies in colour, but is always identical in indi- 
viduals of the same species; it is yellow, ochreous, red, 
violet, blue, &e. 
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Its consistence is variable ; it is composed of minute glo- 
bules, the aggregation of which determines the general tint. 
It is sometimes entire, round, and without segments, as in 
Gromia, Orbulina, &c., which represent at all ages the 
embryonic state of all the other genera. The animal in- 
creases by gemmation, each segment being essentially distinct, 
but connected with the preceding one by a tube or neck. — 
When the body is divided by lobes or segments, the primary — 
lobe, as in the permanent condition of the Gromia, is at first 
round or oval, according to the genus ; once formed it never 
enlarges, but is enveloped externally by testaceous matter. 
The segments, which successively appear, are agglomerated 
together in seven different ways, and these modifications are — 
the basis of M. D’Orbigny’s classification. The discoidal 
forms, as the Rotalia, Rosalina, Cristellaria, &c. are involute, 
like the Nautilus, and divided by septa or partitions, which, 
like the enveloping shell, are perforated. The lobes of the 
» 
body occupy contemporaneously every chamber, and are con- — 
nected by a tube that extends through the entire series. In 
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