ILLEGAL TRAFFIC IN DOPE occurs sporadically today all along the extensive border between Mexico and the United States, from Brownsville, Texas, to San Diego, California. According to reports of the United States Department of Justice, the smuggling of drugs across this border was gradually increasing even prior to Pearl Harbor. These reports further state that since December 7, 1941, Mexico has replaced Manchukuo as a chief source for the unlawful traffic in opium and other similarly dangerous narcotics.2 Near the middle of the wide area comprising the Mexican border lies El Paso, the largest port of entry into the United States and the base of the largest of the American customs agencies, this station controlling the Southwestern region of Arizona, New Mexico, and Texas. Since the legal trade with Red China now has ceased and the illegal greatly abated, the Mexican border has become a main focus of interest for the dope smugglers and the Federal agents trained to apprehend them. What is the nature of the language of the drug addicts with whom both border smugglers and narcotic agents are concerned? The vocabulary of Mexican border dope argot contains many old terms previously used by addicts negotiating with peddlers whose products came from the Orient as well as a large group of newer terms, some of them Spanish, that are used by addicts now buying drugs that derive from Mexico. To understand the present diversity of the narcotic argot heard along the Mexican border,3 it is necessary to review the definitive vocabulary lists which have been already printed, for these glossaries cont.in terms common to narcotic speech wherever it is spoken. In attempting a chronological survey of the character, extent, and quality of dope argot, attention must be called first to an article by David W. Maurer, 'The Argot of the Underworld Narcotic Addict,' which was published in