in the Pacific y S^c. 67 



origin of the wide tracts of chalk and limestone found in vari- 

 ous parts of the globe — the apparent insigniiicance and in- 

 sufficiency of the tiny architects that construct these siiigular 

 edifices when compared with the stupendous results of their 

 labor — all these are points which have long directed to them 

 the researches of the geologist, and given rise to a variety of 

 theories upon the mode in which such innumerable masses 

 of coral have risen from the bottom of -'the vasty deep." 



The inaccurate statements of early voyagers, relative to the 

 rapidity with which coral rose to the surface, seemed to be in 

 a measure corroborated by the accounts brought home by 

 almost every vessel trading to these regions, of new reefs 

 springing up as by magic, in the most frequented tracks. 



Many were in consequence, induced to regard the coral seas 

 as 3ontaining the rudiments of a new continent, which, 

 silently but rapidly, rearing itself above the waste of waters, 

 xVar. destined, at no very remote period, geologically speaking, 

 to equal in magnitude either of those now existing. 



Later, and more systematic examination, however, has 

 shown that such an inference was deduced from very erroneous 

 promises. By observations upon the depths of channels in 

 well known harbors, and the level of reefs in their vicinity ; 

 by the fact that not the slightest increase of the coral is per- 

 ceptible on or around anchors and guns cast upon a reef from 

 a stranded vessel, and known to have remained undisturbed for 

 more than half a century — and by similar means of arriving 

 at an approximation to the truth ; it is now ascertained that 

 the growth of coral is exceedingly slow.* The lapse of many 



* I am inclined to believe that llie increment of the branchino; corals, or at 

 leas', of certain species, is much more rapid than that of the sessile or encrusting 

 genera; having observed such shells as Pecten, Lima, Plicatulu nnd Pedum, of. 

 an inch and a half in length, completely overgrown by the Polyparia, while 

 thei • colors and internal polish were scarcely impaired. These were not lodged 

 as ve frequently see Arcae and Mytili, in accidental cavities, but for the most 

 part imbedded at the divergence of the branches. There are specimens exem- 

 plifvino' this, now in my possession, and also in the Society's collection, in which 

 the branches are enlarged, and sometimis deflected by their envelopment of 

 thefce foreign bodies. The rate of increase in such cases, might be approximately 

 ascertained, by experiments upon the time requisite for shells of this kind to 

 attain a size equal to the imbedded specimens, which it is very likely were 

 lodf^ed upon the corals soon after their expulsion from the parent shell. 



