1912'] 



Resenes of Resins and Oleokesins 



133 



leum ether and the volatile oil. Considerable diflSculty was ex- 

 perienced at the outset in these evaporations due to the tendency 

 of the material to " crawl " over the rim of the vessel. This 

 was entirely overcome by using a thin coating of vaseline on the 

 rim of the vessel. 



The following results were obtained : 



Table I. — Per Cent, of Resene in Resins 



Species. 



Local name. 



Pinus Taeda 



" Palustris 



" Maritima 



" Heterophylla 



" Serotina 



" Echinata 



" Species unknown 



" Sabiniana 



" Laricio 



Loblolly Pine 

 Longleaf Pine 

 Maritime Pine 

 Cuban or Slash Pine 

 Pond Pine 

 Old Field Pine 



Digger Pine 

 Schwarzkiefer 



FROM Different Species 



Per cent. 



Origin. resene. 



North Carolina 4.10 



Florida 5.67 



France 7.37 



Florida 7.38 



Florida 7.65 



North Carolina 8.71 



Central America 8.94 



California 9.66 



Austria 14.05 



In order to test the variation of the amount of resene in trees 

 of the same species two sets of determinations were carried out 

 on trees of different diameters. The results follow : 



Table II. — Pinus Palustris (Longleaf Pine). 



Table 



To determine possible variations in the per cent, of the resene 

 in different seasons of the same year two trees were selected, 

 one each, Pinus Palustris, tree No. 2, Table II, and Pinus Het 

 erophyllaj tree No. 2, Table III. Beginning in the early spring 



