a. The Discovery of Ergot Alkaloids.—Constituents of ergot, 
Claviceps purpurea (Fr.) Tul., a relatively primitive ascomycete, 
in one of the phylogenetically most advanced angiosperm 
families was unexpected and is of great chemotaxonomic inter- 
est. Suspicion that fungal spores might have contaminated the 
convolvulaceous seeds was experimentally ruled out (Taber and 
Heacock 1962), and the discovery of the same alkaloids in fresh 
leaves, stalks, and root of /pomoea violacea and, to a minor 
extent, in leaves of Turbina corymbosa indicated that these 
constituents are produced by the tissue of the morning glories 
themselves, not by infecting fungi (Shinners 1965). 
Studies have shown the presence of these ergot alkaloids ina 
number of horticultural “varieties” of Jpomoea violacea and 
other species of /pomoea, as well as in the related genera 
Argyreia and Stictocardia (Chao and Der Marderosian 1973; 
Der Marderosian and Youngken Jr. 1966; Hylin and Watson 
1965; Taber et al. 1963). 
There are folklore references to psychotomimetic uses of 
Ipomoea carnea Jacq. in Ecuador, where its common names, 
borrachera and matacabra, refer to its inebriating or toxic 
effects. Ergot alkaloids have been isolated from this species 
(Lascano et al. 1967; Naranjo, 1969; Naranjo et al. 1964). 
The nomenclature and taxonomy of the Convolvulaceae are 
in a state of extreme confusion, especially as to delimitation of 
genera (Der Marderosian 1965; Schultes 1970c, 1980; Shinners 
1965). Turbina corymbosa occurs in the southernmost United 
States, Mexico and Central America, some of the Caribbean 
islands and the northern coast of South America. It has at least 
nine synonyms, of which /pomoea sidaefolia (HBK.) Choisy and 
Rivea corymbosa are the most frequently employed. /pomoea, 
comprising upwards of 500 species in the warm temperate and 
tropical parts of the hemisphere, is a genus of climbing herbs or 
shrubs, rarely semi-aquatic. /pomoea violacea, often referred to 
by its synonyms /. rubrocaerulea Hook. and J. tricolor Cav.., is 
represented in horticulture by a number of “varieties”, such as 
Heavenly Blue, Pearly Gates, Flying Saucers, Wedding Bells, 
Summer Skies, and Blue Stars — all of which contain the 
hallucinogenic ergot alkaloids (Der Marderosian 1967b), 
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