COCAINE 359 



present the usually undesirable effect of dilating the blood-vessels or 

 at feast of not constricting them as does cocaine; hence some of 

 them are almost always employed in conjunction with'epinephrin. 

 They owe their origin to the discovery that local anesthetic action 

 of cocaine is due to the radical of benzoic acid in combination with a 

 nitrogen-containing basic group. The simplest of these compounds, 

 anesthesin, propaesin and cycloform, are, respectively, ethyl, propyl 

 and insobutyl esters of para-amino benzoic acid, CeH^NEyCOOH; 

 orthoform and orthoform-new are the methyl esters of oxy-amino 

 benzoic acids, C 6 H 3 (OH)(NH2)(COOH). All of these are too weak 

 or too insoluble in water to be useful for hypodermic injections; 

 they are used as local applications. Procaine is a compound of para- 

 amino-benzoic acid with diethyl-amino-ethyl alcohol; its salts are 

 readily soluble in water. Stovaine and alypin are esters produced 

 by combination of benzoic acid with derivatives of an amino-amyl 

 alcohol ; their salts are easily soluble in water, but they are much more 

 toxic than the preceding compounds. Beta-eucaine is a compound 

 of benzoic acid and derivative of oxypiperidin. Tropacocaine is much 

 more closely related to cocaine than are the preceding. 



Cocaine Substitutes. The relative toxicity of the synthetic sub- 

 stitutes for cocaine, included in New and Nonofficial Remedies, 1919, 

 p. 27, are exhibited in the following table: 



Anesthesin Non-toxic 



Propaesin Practically non-toxic 



Stovaine From one-third to one-half as toxic as cocaine 



Alypin One-half as toxic as cocaine 



Procaine Less toxic than stovaine or alypin 



Beta-eucaine hydrochloride Much less poisonous than cocaine 



Tropacocaine hydrochloride One-half as toxic as cocaine 



ZYGOPHYLLACE^, OR CALTROP FAMILY 



The plants are mostly herbs and shrubs which are widely dis- 

 tributed in warm-tropical regions. The leaves are mostly opposite, 

 pinnate and stipulate. The flowers are perfect, regular and j mostly 

 5-merous. The fruit is usually capsular. The hairs are usually 

 simple and unicellular, occasionally there is a metamorphosis of the 

 wall to form a resinous excretion. A similar modification of the walls 

 of the epidermal cells of the stipules occur in Larrea tridentata, a 

 plant common in Mexico and southwestern United States and known 

 as Creosote bush. True glandular hairs do not occur in the plants of 

 this family. Mucilage cells and tannin-secreting cells are also 

 occasionally present. The tracheae usually have simple pores and in 



