Note
This paper reports a study of specific marine snow aggregates - those derived from abandoned larvacean houses (Alldredge 1972, 1976, 1977). From differences measured in the aggregates and their associated microbial communities, we propose a life history divided into 3 well-defined successional phases. These phases are described and the microbial communities associated with the aggregates are compared to substrata associated communities and to surrounding water communities under different hydrographic regimes.