Nuclear numbers in encysted dormant embryos of differentArtemia salina populations

Summary The number of nuclei in dormant cysts from world-wide populations of the brine shrimp,Artemia salina (L.) was determined. These nuclear numbers proved to be quite constant considering the diversity of geographical localities, ploidies, and modes of reproduction represented by these populations. We believe this constancy indicates a tight coupling between the development and dormancy of these embryos. Chromosome counts onArtemia from Jamnagar, India indicated this population to be triploid.We wish to thank Dr.T. Iwasaki for supplying cysts of the Aio Machi population, Dr.C. Barigozzi for cysts from Sete and Comacchio, and Dr.G. Stephens for cysts from Jamnagar. This research was supported by a grant from the U.S. National Science Foundation No. GB-40199.