162 SCIENTIFIC AND APPLIED PHARMACOGNOSY 



Allied Plants. The bark of the black walnut (Juglans nigra), 

 somewhat resembles butternut bark, but is more coarsely striate and 

 the fractured surface is more uniformly brown. 



Literature. Holm, Merck's Kept., 1918, 27, pp. 115 and 168. 



CORTEX FRUCTUS JUGLANDIS. Cortex Nucum Juglandis Viridis, 

 English Walnut Shells. The hulls (outer portion of the pericarp) 

 of the fruit of the Persian or English walnut (Juglans regia) have 

 been used in medicine in the fresh and green condition. The dried 

 hulls have been recently imported under the name of " vegetable 

 shells " apparently for the purposes of using them in the ground 

 condition as an adulterant. 



The dried hulls, or " shells," consist of pieces or fragments com- 

 posed for the most part of the outer layers of the pericarp, i.e., the 

 epicarp and sarcocarp. The pieces are more or less irregular, invo- 

 luted and shriveled, from 5 to 35 mm. in diameter, and break with a 

 short fracture. Some of the pieces are marked by the stem-scar or 

 still have attached to them portions of the stem. Externally, the 

 epicarp, or outer layer, is rather smooth, though coarsely wrinkled, 

 marked by numerous small dots, and varies in color from light to 

 dark brown. The sarcocarp, or inner layer, is somewhat spongy, 

 dark brown or blackish-brown in color, and more or less fibrous, due 

 to the shrinking of the parenchyma from the fibrovascular bundles. 

 The taste of the hull is markedly acid and somewhat bitterish, but 

 the odor is not very pronounced or characteristic. 



The microscopical characteristics of the powder are illustrated 

 in Fig. 71. 



Literature. Kraemer, Amer. Jour. Pharm., 1911, p. 377. 



BETULACE^, OR BIRCH FAMILY 



A group of 6 genera of monoecious trees or shrubs. They are com- 

 mon to both hemispheres. The two genera of greatest importance 

 are Betula or birch, and Corylus or hazelnut. The birches are 

 extremely hardy and some grow within the Arctic circle. They find 

 a great many uses. A volatile oil, closely resembling true oil of win- 

 tergreen, is obtained from the twigs and bark of the trunk of the 

 sweet or black birch (Betual lenta) , a tree growing in the eastern por- 

 tion of the United States. The bark of the white birch serves a 

 number of useful purposes, slabs of it being used for the thatching of 

 roofs, the outside covering of boxes for window gardens, as well as a 

 variety of other purposes. It contains a yellow coloring principle, 

 making it serviceable in dyeing, and sufficient tannin to make it 



