700 Transactions of the American Institute. 



FOSSIL rV'ORY. 



It is said that the tusks of at least one hundred mammoths, or 

 about forty thousand pounds of ivory, are bartered for every j^ear 

 in New Siberia. Notwithstanding the large amount carried away, 

 the supply does not seem to diminish. These remains are scattered 

 along the valleys and near the mouths of great rivers; and in a 

 number of instances the mammoth entire has been discovered, with 

 its skin protected by a double covering of hair and wool, and its 

 flesh in such a state of preservation as to afford food for dogs and 

 wild beasts. Whatever the cause of the Siberian mammoth's death, 

 it is certain they were suddenly enveloped in ice, which has not 

 been disturbed since they were first entombed. 



THE TORTOISE. 



Dr. Deschamps has, after minute investigation, arrived at the 

 eonclusion that the shell of the tortoise is a calcareous metamor- 

 phosis of the derma, the fibers of elastic tissues having the property 

 of admitting of incrustation with calcareous salts. It is well known 

 that any osseous surface exposed to the air mortifies, owing to the 

 destruction of the periosteum, the membrane which supplies calca- 

 reous matter. This is precisely what happens when a scale of the 

 tortoise shell falls off; the bone below mortifies and falls off too, 

 and both are regenerated b}'^ the action of the skin, divided into fila- 

 ments, which penetrate into all the grooves. In order that this 

 action may be safely performed without any necrosis of the bone, 

 the scale does not fall off immediately, but opens very gradually, 

 like the lid of a box, and thus affords time for the reproduction of 

 the new scale. Dr. Deschamps has collected some curious facts 

 about this animal's tenacity of life. Francesco Redi having deprived 

 the tortoise of his brain, found he could live six months without it; 

 he cut off the head of another, but even this did not prevent the 

 heart from beating for twelve days after the operation. 



RHUBARB JUICE. 



At a recent trial of a case before the Circuit Court of Middlesex 

 county, N. J., in which the matter of dispute was the value of the 

 so-called " Myatt Lynnseus Wine Plant," Prof. G. H. Cook, of Kut- 

 gers College, testified that he was acquainted with the plant bearing 

 the botanical name of Rheum Raphonticum. The Myatt Lynnasus is 

 one of the varieties cultivated in gardens, and used for making pies. 

 It is not known as a wine plant. Pure wine is the fermented juice 



