Wallis and Melnick (3) reported the stability of 25 ECHO viruses and 7 coxsackie viruses in the presence of 1M MgC12 or CaCl2. Melnick (1) discussed the stability of enteroviruses with divalent ions and also related the importance of pH (2). To date, there have been but scanty reports involving cationic stabilization of avian viruses. This report describes the stability of 3 avian viruses in cationic solutions. The Phelps strain of the chicken-embryo-lethal-orphan (CELO) virus, the LaSota strain of Newcastle disease virus (NDV), and infectious bronchitis virus (IBV) were stored at 4 C in demineralized distilled (DD) water and in monovalent and divalent cationic solutions prepared in DD H20 at pH 7.0. All 3 viruses were assayed to determine titers at the time of storage, and tested again after various intervals. Results are in Table 1. CELO virus was checked periodically over a 24-hour period. In solutions of 0.5M NaCI, KC1, CaC12, or MgCl2, results indicated complete stability during the 24 hours. Also there was no loss of infectivity when stored in DD H20. NDV stored in DD H20 as well as in 0.1M and 1M solutions of NaCl or CaC12 was tested over a 7-day period. After 12 hours a fraction of the original infective virus remained in the 0.1M solution of NaCI and in both molar solutions of CaCl2, and by the seventh day there was no evidence of viable virus in these three suspending solutions. No infective virus was lost through the first 2 days in DD H20 but there was a 90% decrease by the third day that remained constant through the seventh day. There was no loss