CRUDE DRUGS. 587 



fruit is derived. Most of the vanilla used in the United States 

 comes from Mexico. Some of the Reunion (or Bourbon) fruit 

 is now also entering the market. For method of curing the fruit 

 see p. 245. 



Mexican Vanilla. Pods narrow, linear, about 20 cm. long, 

 7 mm. in diameter, 4 mm. thick ; apex oblique, with a circular 

 scar; base curved or bent, with a slightly enlarged circular scar; 

 externally blackish-brown, longitudinally wrinkled, moist, glossy, 

 sometimes with acicular crystals or monoclinic prisms ; pericarp 

 about I mm. thick; internally dark brown, i-locular, with numer- 

 ous seeds embedded in a dark-colored pulp ; seeds anatropous, 

 ovoid, flattened, 0.2 to 0.3 mm. in diameter, black, iinely retic- 

 ulate, reserve layers wanting, embryo shrunken ; odor and taste 

 distinct. 



Bourbon Vanilla resembles the Mexican Vanilla, but is 

 about two-thirds as long and the outer surface is usually covered 

 with crystals. 



Inner Structure. See Figs. 256, 313. 



Constituents. An odorous crystalline principle, vanillin, 

 from 1.5 to 3 per cent.; an odorous, balsamic or resinous prin- 

 ciple, which is developed during the process of curing and to 

 which the peculiar odor of vanilla is due; sugar about 10 per 

 cent.; fixed oil about 10 per cent.; calcium oxalate in raphides ; 

 ash about 5 per cent. 



Vanillin or methyl protocatechuic aldehyde is manufactured 

 on a large scale from eugenol or coniferin. It occurs in white, 

 acicular crystals, which are sparingly soluble in water, soluble 

 in aclohol and glycerin, the solutions being colored blue with 

 ferric chloride. Vanillin may be formed as a result of certain 

 oxidation changes rather than through the action of a ferment 

 like emulsin which, as has been recently shown, does not exist in 

 the fresh pods (Fig. 128). 



The fruits of a number of species of Vanilla yield vanillin, 

 which is also found in the Orchid Selenipedmin Chica, of Pan- 

 ama; the fruit of Rosa canina, of Northern and Middle Europe; 

 the flowers of Spircca Uhuaria; the balsams and resins of the 

 genus Tohiifcra; in the seeds of Lupinus alhus, of Europe, which 

 is cultivated ; and in the bulbs of Dahlia. 



