24 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



full-grown cocoanut trees, without destroying each other's symmetry, were mingled into one wood. 

 A beach of glittering white sand formed a border to these fairy spots." 



" The long strips of land forming the linear islets have been raised only to that height to which 

 the surf can throw fragments of coral, and the wind heap up calcareous sand. The solid plat of 

 coral rock on the outside, by its breadth, breaks the first violence of the waves, which otherwise 

 in a day would sweep away these islets and all their productions. The ocean and the land seem 

 here struggling for mastery. Although terra Jirma has obtained a footing the denizens of the water 

 think their claim at least equally good. lu every part one meets hermit crabs of more than one 

 species carrying on their backs the shells which they have stolen from the neighboring beach. 

 Overhead numerous gaijnets, frigate-birds, and terns rest on the trees ; and the wood, from the 

 many nests and from the smell of the atmosphere, might be called a sea-rookery. The gannets, 

 sitting on their rude nests, gaze at one with a stupid yet angry air. The noddies, as their name 

 expresses, are silly little creatures. But there is one charming bird ; it is a small snow-white tern, 

 which smoothly hovers at the distance of a few feet above one's head, its large black eye scanning, 

 with quiet curiosity, your expression. Little imagination is required to fancy that so light and 

 delicate a body must be tenanted by some wandering fairy spirit." 



" The next day I employed myself in examining the very interesting yet simple structure and 

 origin of these islands. The water being unusually smooth, I waded over the outer plat of dead 

 rock as far as the living mounds of coral, on which the swell of the open sea breaks. In some of 

 the gullies and hollows there were beautiful green and other colored fishes, and the form and tints 

 of many of the zoophytes were admirable. It is excusable to grow enthusiastic over the infinite 

 numbers of organic beings with which the sea of the tropics, so prodigal of life, teems, yet I must 

 confess I think those naturalists who have described, in well-known words, the submarine grottoes 

 decked with a thousand beauties have indulged in rather exuberant language." 



" Every single atom, from the least particle to the largest fragment of rock, in this great pile, 

 which, however, is small compared with very many other lagoon islands, bears the stamp of having 

 been subjected to organic arrangement. We feel surprised when travelers tell us of the vast 

 dimensions of the pyramids and other great ruins, but how utterly insignificant are the greatest of 

 these when compared to these mountains of stone accumulated by the agency of various minute 

 and tender animals ! This is a wonder which does not at first strike the eye of the body, but, 

 after reflection, the eye of reason." 



The foregoing extracts give a complete picture of the typical coral atoll, and, as I have said, we 

 require simply to make a few changes in the dimensions to make them exactly apply to Caroline 

 Island. The frontispiece, which is derived from the survey made at my request, will give the 

 necessary changes at a glance. 



To this I add a brief description furnished by Lieutenant Qualtrough. 



"Caroline Island, or chain of islands, is of coral formation of the lagoon type, and in shape 

 is an irregular elongated oval ; it is 5f miles long from NNE. to SSW. and its circumference, meas- 

 ured on the outer or inclosing reef, is approximately 13 miles. The greatest breadth is at the south- 

 ern end, where it measures Ij^ miles, and the average width may be placed at three quarters of a 

 mile. 



"The atoll consists of a chain of twenty-five little islets, well covered with trees and shrubbery, 

 the whole forming a quiet scene of grove and lake, charmingly set off by the contrasting ocean. 

 Between the patches of verdure there is a flat, water-covered table of coral rock, which is covered 



