Papaver curviscapum Nab. (Papaveraceae), a biennial poppy occurring in rocky fissures at about 1500 m in South East Turkey and North Iraq (section Miltantha, closely related to alkaloid-rich species such as P. fugax Poir. and P. tauricola Boiss.), had only one previous report concerning its alkaloids, identifying allocryptopine and cryptopine in small amounts from Iraqi herbarium samples with other unidentified alkaloids indicated. In this communication, we report the isolation of alkaloids from a larger sample collected in Turkey. The major tertiary base present proved to be the new crystalline alkaloid 1-methoxyallocryptopine (1), C22H25NO6 (previously known synthetically). The related known alkaloid 1-methoxy-13-oxoallocryptopine (2) was also obtained in lesser amounts. Other protopines isolated were allocryptopine and protopine. The dominant quaternary alkaloid was berberine, which had previously been reported as the major alkaloid of another species of the Miltantha section, namely P. polychaetum Schoot et Kotschy.