344 THE POPULAR SCIENCE MONTHLY. 



the slightest crevices and open spaces in the hones, was in every case 

 roctf-fibers. I took out of the pulp-cavity of one tusk a compact cone 

 of these rootlets. I have seen precisely the same thing when opening 

 a small drain-pipe which had become choked with the roots of a tree. 



Two facts have much impressed me the great geological antiquity 

 of the mastodons as a race, and the very recent existence of the indi- 

 vidual we are discussing. The race began in Miocene time ; this in- 

 dividual lived in the Quaternary age, and well up into the soil-making 

 period. There is little if any differentiation of the molars. The cusps, 

 or teats, on the crown are high and prominent, although 1 think it 

 must have been one of the very last of its tribe. Though the race 

 came before those great castors now extinct, this individual was con- 

 temporary with the existing beaver, and doubtless with the aboriginal 

 man. 



It is singular that in the present controversy respecting the sub- 

 sidence of a part of the eastern coast-line of the United States, I have 

 never seen the testimony of the mastodon put in evidence. As already 

 said, this animal has run through a long stretch of geologic time. I 

 saw a tusk taken from the Trenton gravels of New Jersey which be- 

 long to the ice age, or glacial epoch. I have part of a tusk taken from 

 the shore in Monmouth County, New Jersey, after a storm. This 

 storm from the sea had washed away the drift which covered an an- 

 cient swamp, in which this relic, with other bones, had been entombed. 

 But that swamp had been far inland, sufficient for a depression to 

 exist far enough away from the action of the sea to enable it to sup- 

 port a non-marine, sub-aquatic vegetation. The subsidence had al- 

 lowed the sea to come up and uncover that creature's grave. Last 

 summer, at Long Branch, I saw a fine mastodon's tooth which was 

 taken up by fishermen out at sea. I have also some fragments of a 

 mastodon's tooth, besides an almost entire one of remarkable size. I 

 consider it the sixth,* or last tooth developed. It was given me as 

 coming from Long Branch, where it was obtained so long ago that 

 its history was forgotten. I detected upon it the microscopic skele- 

 tons of marine Bryozoa, the same species that I have often found on 

 the shells of our modern oysters. This tiny animal can only attach it- 

 self to a clean anchorage in the clear sea-water. Hence this tooth was 

 evidently got from the sea ; and, more, its old grave of mud or peat 

 was long ago invaded by the sea and churned up, so as to float it away, 

 leaving the tooth on the clean, sandy ocean-floor. 



* Not counting the tusks, the elephant has only eight teeth in his mouth at any one 

 time two molars on each side of each jaw. The forward tooth of each pair is pushed 

 forward until it disappears. The back one then is pushed forward, and replaces the one 

 lost. This goes on until six molars have appeared on each side of each jaw, so that the 

 full-aged animal has in its life-time twenty-four molars. The tusks are monstrously de- 

 veloped incisors. While the true elephant has normally but two tusks, the male mas- 

 todon has four, two small ones in the lower jaw, which, however, are shed before adult 



