Further Investigations on the Preservation of Molds

Various methods have been used for preserving fungi and other microorganisms. This paper gives further evidence of the value of the procedures now in use, particularly that of lyophilization. Three reports have already appeared from this laboratory, Raper and Alexander (1945), Fennell et al. (1950) and Mehrotra and Hesseltine (1958). As a continuation, all species of fungi except the Aspergilli, the Penicillia and the yeasts, that have been in the ARS Culture Collection for a long time, were tested for viability. Also, some Actinomycetes received and lyophilized prior to 1949 were examined. Most of the cultures have been in lyophil for 17 years. Some Mucorales that had been preserved in 1945 by the mineral oil overlay method were also tested. Additional cultures of Mucorales on dried slants were covered with warm melted