THE MUSEUM. 



79 



north, into which sediment, held in sus- 

 pension was deposited. In the pro- 

 cess of time this deposit became a huge 

 hill, or rather a succession of hills, reach- 

 ing nearly to the surface. Then the 

 coral insect was carried thither, and, at 

 length the deposit of mud became a 

 series of coral islands. The work of 

 the coral insect was continued until the 

 islands were united into one long reef; 

 then, bending at each extremity towards 

 the north, it finally united each end 

 with the mainland and formed a la- 

 goon of stagnant water in the interior. 



The creation of this reef still further 

 detiected the Gulf Stream, and, by an 

 exactly similar process, a second reef 

 was created enclosing a similar lagoon; 

 then, still further to the south, came 

 the third, then the fourth, and then the 

 fifth. And now the same influences 

 are at work in the long string of islands 

 off the southern extremity of Florida, 

 and, after the lapse of a sufficient 

 number of years, a sixth reef will be 

 added and the peninsula of Florida 

 will extend still farther to the south. 

 So far as we can foresee, this will con- 

 tinue until the Gulf Stream will be 

 shut out from the Gulf of Mexico, the 

 results of which we cannot predict. 



But to return to the phosphate. 

 These lagoons, as soon as the water be- 

 came still, began to teem with animal 

 life peculiar to the geological period 

 and their own physical conditions. 



Now nearly every living organism 

 secretes from its food, or drink, 

 or from the element in which it 

 Hves, certain mineral substances with 

 which to build the framework of its 

 system. The principal minerals thus 

 secreted are carbonate of lime, phos- 

 phate of lime, and silica. In all of the 

 vertebrates, carbonate of lime greatly 



preponderates. In some of the- mol- 

 lusks, carbonate of lime forms the 

 greater portion ; in others a greater 

 percentage of phosphate of lime is 

 found, and in some, as the Lingula, for 

 instance, the shell ,is composed almost 

 entirely of it. Certain of the Foramin- 

 iierx also secrete phosphate of lime in 

 large quantities; as do certain Infuso- 

 rise. 



We know that in geological ages, 

 certain forms of animal life existed, 

 which secreted carbonate of lime in 

 such quantities, and in such numbers 

 that \ast deposits of that substance 

 were formed by the death and disinte- 

 gration of the respective forms; and it 

 seems very probable that in the lagoons 

 already described and which from vari- 

 ous causes became filled, there existed, 

 in certain localities, species of Mollusks 

 which formed their external shells of 

 phosphate of lime, and that the death 

 of these Mollusks and the consequent 

 disintegration of their shells created the 

 deposits which we now know as phos- 

 phate rock. 



Dusky Grouse- 



Dendragapus Obscurus. 



The dusky Grouse is resident, and 

 by no means uncommon in the heavily 

 wooded ranges of the Gallinass Valley 

 in North Central, New Mexico. Its 

 immigrations if they can be properly so 

 called, seems to be from the Aspen 

 Groves in the foot-hills, where they 

 nest, to the Coniferous belts during 

 winter. They are hardly common 

 enough to be found in the markets. 

 Still they are excellent eating though 

 they at some seasons at least have a 

 somewhat musky flavor, which is by 

 no means unpleasant. They are tame 



