dant resin that forms in and flows from our pines, and sometimes 

 accumulates in hardened masses under the bark and around the 

 roots of the trees. The resins are bodies almost unaffected by 

 the ordinary processes of decay, or by anything except a high 

 heat. Hence in the change of wood to lignite or brown-coal, 

 any resinous matter present in the wood remains practically 

 unaltered ; and it is not unusual to find a perfectly black lignite 

 seamed or specked with bright yellow resin. It is true that the 

 resin has undergone some change; it is hardened, and some 

 chemical alteration has taken place, but nothing that essen- 

 tially changes its appearance. These fossil resins, so called, 

 are beautiful and interesting bodies, the most notable being the 

 celebrated substance amber, about which has gathered so much 

 of romance and fable. But besides amber, there are many va- 

 rieties of fossil and semi-fossil resins, resembling amber in aspect, 

 but less hard and less valuable. Among these are the copals, 

 which are quite abundant in some parts of Africa and the East 

 Indies, and are largely imported for the manufacture of fine 

 varnishes. The New Zealand "Kauri gum," as it is usually 

 called, which is not a gum, however, but a resin, is also exten- 

 sively used for such purposes. Examples are shown of both 

 these substances. Attention is called to the specimen No. 9632, 

 from New Zealand, which shows the occurrence of a golden- 

 yellow fossil resin in a jet-black lignite, as described above. 



These resinous bodies belong to the later periods of geological 

 time. Some hard ambers are found in Cretaceous lignite-beds; 

 the true amber of jewelry is of Tertiary age; and the copals are 

 mainly Post-tertiary (or Quaternary) ; and these pass gradually 

 into the resinous exudations of modern trees. 



D. S. Martin. 



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