A study of larval fishes in the Lower Mississippi River, river miles 505-525, was conducted from April through October 1980. The objectives of this study were to assess the relative importance of dike fields, revetted banks, and other habitats to fish larvae and to characterize the seasonal changes in local distribution of ichthyoplankton within a dike field. With respect to larval fish exology, the results of this study may be representative of the Lower Mississippi River mainstream in general. Shads and herrings were abundant and common in all locations, while other taxa exhibited clear affinities for certain habitats. The Lower Cracraft Dike Field exhibited variability in larval fish diversity and abundance throughout the spawning season. During high to moderate river stage conditions (April through June), larval fish diversity was high and abundance was greater at open water stations than nearshore stations.