manfred,
Crot-c is Crotalus cascavella and in Boericke MM that is mentioned in the Relationship paragraph of Crotalus Horridus.You can find Crot-c in the Book "The Encyclopedia of Pure Materia Medica" ,Edited by T.F.Allen.

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Dr.S.K.Pattnaik,HMD,M.D(Alt.Med),Ph.D
Chairman,Indian Council for Holistic Health Care
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