NATURAL HISTORY. 



497 



These extremities, when pressed, 

 give out a white unctuous fluid 

 resembling milk, which has a sour 

 tHste. It was formel}'^ thought to 

 be the seed and nutritious juice of 

 the coral plaut. 



Tlie substance of coral is hard 

 as well in the sea, as when out. 

 The red kind is red from the first, 

 and it is u singular circumstance, 

 that the ancients should have en- 

 tertained these two erroneous opi- 

 nions, which the mo^t simple exa- 

 mination would have falsified. — 

 The central part or axis of the 

 coral is hard, of a firm solid texture, 

 even, and lamellated ; and hence 

 capable of taking the finest polish. 

 This is inclosed by a paler coloured 

 bark of a granulated texture, inter- 

 spersed with holes in the form of 

 stars with eight rays. In the coral 

 of the largest size sometimes is 

 found a kind of joint or union 

 between the different pieces of 

 which it is composed, the^^e having 

 the appearance of tubes of some 

 length, lying one above the other. 

 In the analysis of coral we obtain a 

 small quantity of gelatinous animal 

 matter, a large proportion of car- 

 bonate of lime, and a little iron. 

 The different colours of this bt-au- 

 tiful marine ^jroduction seem to 

 depend on the different degrees of 

 oxidation of the iron, and various 

 proportions of it in union with the 

 animal matter. The discovery of 

 polypi gave the clearest idea of 

 the origin and growth of coral. 

 These animals, the last in the scale 

 of animated nature, form for them- 

 selves small nests sufficiently solid 

 to shelter and protect them. These 

 soft and delicate animals, surround- 

 ed by an element in a constant 

 state of agitation, and exposed to 

 the attacks of their numerous ene? 



Vol. LIV. 



mies, were instructed by nature to 

 form for themselves a covering 

 capable of resisting the percussion 

 of the sea, and affording them a 

 retreat in the moment of danger. 



These coralligenous polypi are 

 only a few lines in length ; their 

 bodies elongate and ramify into 

 eight delicate threadlike branche* 

 around the mouth. These are the 

 arms and legs of the animal, which 

 it can extend and spread out at 

 will to a considerable distance in 

 search of its food. They are 

 analogous to the horns of the sufiil. 

 The curious manner of propagation 

 of polypi, so different from that of 

 other larger and more perfect ani- 

 mals, is well known ; on examining 

 minutely the gelatinous bodies of 

 these polypi, a great number of 

 grains, or littlebuds, are discernible, 

 covering the surface ; these elongate 

 themselves, increase in thickness, 

 diverge and spread inall directions, 

 and become young polypi. Scarcely 

 are these developed, before a new 

 series of sprouts appears from thei?^ 

 small bodies by the increase and 

 growth of the small buds on their 

 surface By this ra[)id succession 

 the family is propagated in every 

 direction, forming as it were a 

 genealogical tree of existing gene- 

 rations. It is well known how, 

 from the soft nature of their bodies, 

 these animals are enabled to unite 

 and engraft with each other in the 

 same manner as plants ; and one 

 branch of these animalculee so 

 engrafted lives and regenerates 

 another. Even one single animal 

 may detach itself from the family 

 tree, and estal)lish on another spot 

 a new family with its various 

 branches. While large animals 

 have bones for the support of the 

 softer parts, and shell fish are pro- 



2 K tected 



