THE JOURNAL OF PHARMACOLOGY. 9 



are to be found. These are very various — column-shaped, dice-shaped, 

 cuboidal and octahedronal forms being found. Sometimes twin crystals 

 are seen. 



The hairs are very characteristic ; both simple and glandular types 

 abound. Most of them are multicellular. The simple hairs end in 

 straight non-secreting points, while the others have many-celled heads 

 which contain resin-like secretions. The simple hairs vary greatly in 

 length and diameter. In length they often measure from 100-400 micra, 

 and often average between 20 and 50 mlcra at the base. The wall is 

 usually smooth. The glandular hairs may be even larger than the simple 

 ones. 



Epidermis cells are smooth, mostly wavy in outline, save over the mid- 

 rib, where they are elongated and pointed. 



Stomata are frequent, being found on both surfaces. They average 

 about 40 micra in their longest diameter and about 30 in breadth ; the 

 neben-zelleii average three to four, though there may be at times as many 

 as six. 



Fibers are not common. Fragments of spiral vessels are not infrequent. 

 Occasionally pollen grains may be found in the powder. 



According to Tschirch the crystals are diagnostic alone and serve as a 

 means of differentiating this leaf from other leaves of the narcotic group. 

 Thus hyoscyamus has at least four kinds of crystals ; stramonium has 

 crystal glands ; belladonna, crystal sand, and digitalis, no crystals. 



Belladonna Leap. 



General morphology of the leaf. — The leaves are ovate with sharpened 

 apex, narrowed at the base, from 20 to 30 cm. in length and about 10 to 

 12 cm. broad. The margins are entire and the surface is smooth ; here 

 and there a few hairs may be seen on the veins of the under side and also 

 on the petiole. In this latter situation they are more abundant and larger. 

 The younger leaves are more abundantly provided with hairs, and these 

 also have small-stalked glandular cells. The upper surface is dark-green, 

 the lower lighter, grayish-green, showing whitish spots ; these locate the 

 cells containing the crystal sand of oxalate of calcium. 



Anatomy of the leaf. — Both upper and lower surfaces of the leaf show 

 stomata. These are oval. A cross section shows the epidermis, with 

 slightly thickened outer cutinized wall ; palisade tissues on the upper side 

 only in a single row filled with chlorophyl grains ; the mesophyl paren- 

 chyma with cells containing ^the crystal sand and cross sections of the 

 fibro-vascular bundles, which are more prominent in the lower parts of the 

 leaf. 



Powder. — The powder is brownish to dark green. The most prominent 

 features of a No. 60 powder are the epidermis cells. Other elements are 



