ADDENDA 475 



nesium. The material was easily fusible, with faint green 

 flame, and is readily soluble in acids. It gives the charac- 

 teristic reaction for phosphoric acid, and also gives a test 

 for magnesium. In the closed tube it secretes abundant 

 water and emits a distinct odour of ammonia. 



THE CHARACTERISTICS OF IVORY ARE AFFECTED BY THE 

 HABITAT OF THE ELEPHANT 



The ivory from elephants of the Northeastern Uele in the 

 Congo, which roam over a region of dry brush, or of thinly 

 wooded valleys, where plenty of food is to be had, is more 

 massive and less hollow than that from the elephants of the 

 forests. Here, where the food is more succulent, the ivory 

 is, as a rule, more hollow and less dense, and the nerve only 

 traverses about a third of the length of the tusk. Elephants 

 having tusks, each of which weighs from 50 to 100 lbs., are 

 fairly common near Faradje, Dungi, Gombari, Vankerck- 

 hovenville, and Aba in the Congo.* 



MASTODON OR MAMMOTH REMAINS 



An early notice of the finding of mastodon or mammoth 

 remains in the western and southern parts of the United 

 States appears in the writings of Thomas Jefferson. The 

 following extract shows that the Indians of this time, about 

 1782, rivalled the Alaskan Indians of our day in their ability 

 to invent a description of living mammoths. Jefferson 

 writes if 



*'It is well known that on the Ohio, and in many parts 

 of America farther North, tusks, grinders, and skeletons of 

 unparalleled magnitude are found in great numbers, some 

 lying on the surface of the earth, and some a little below it. 



*Coinmunicated by Mr. Herbert Lang, of the American Museum of Natural History 

 Expedition to the Congo. 



t" Notes on the State of Virginia," by Thomas JefiPerson, Philadelphia, 1788, p. 41. 



