In the first alkaloid investigation of the genus Cryptantha (Boraginaceae), pyrrolizidine alkaloids were identified from C. cana, C. clevelandii, C. confertiflora, C. flava, C. fendleri, C. leiocarpa, C. thyrsiflora, C. virgata and C. virginensis. Six perennial species from section (or subgenus) Oreocarya were similar in their alkaloid content, which was dominated by lycopsamine and intermedine and in some species with their acetyl derivatives. In two other species from this section, amabiline and tessellatine (heliospathine) were also major components. In contrast, in three annual species from section (or subgenus) Krynitzkia, the major pyrrolizidine alkaloids were angelylretronecine and echiumine derivatives. New pyrrolizidine alkaloids found were threo-2″,3″-dihydroxyechiumine, erythro-3″-chloro-2″-hydroxyechiumine and 2″,3″-epoxyechiumine. bl. © 1993.