A STUDY OF THE EARLY LIFE STAGES OF THE LOBSTER, Homarus americanus, USING SCANNING ELECTRON MICROSCOPY (SEM)¹

With the accelerated interest in commercial lobster production, knowledge of the early developmental stages is important. There are limited observations and data pertaining to the first 4 life stages of the American lobster Homarus americanus. The existing data can be strengthened through use of the scanning electron microscope. Current sketches are based on light microscopy and observations without magnification. A series of micrographs of the first 4 life stages with reference to existing drawings are presented. The first 3 larval stages float in the pelagic environment while the fourth stage sinks to the bottom and assumes the characteristic bottom‐dwelling behavior of adult lobsters. Characteristics pertaining to number and loss of appendages, size and division of the body, spines, division of the uropod, development of the walking legs and antennae are stressed. A two‐dimensional drawing will be presented utilizing the existing published data for the life stages and the scanning electron micrographs.