Allometric Studies on Energy Relationships in the Spider Crablibinia Emarginata(leach)

Allometric plots were used to separate Libinia emarginata into three male growth stages; immature, prepubescent, and mature; and two female stages; immature-prepubescent, and mature.2. The existence of two optional prepubescent molts in males allows a 2.75-fold variation in mature (non-molting) length; and one optional molt in females allows a 1.75-fold variation in mature length.3. Because of the very great size range in mature crabs (especially males), there are apparently two reproductive strategies; small mature size and several reproductive years, and large size with one reproductive year.4. The regression of routine oxygen consumption, measured over the entire size range of this crab, exhibits virtually the same slope (0.81) as found by Zeuthen (1953) for crustacea in general.5. The maximum capacity of the stomach, and the maximum hepatopancreas wet weight follow the same allometric relation (slope or a) as the oxygen consumption, in agreement with the idea that metabolic rate is reflected in the size of the digestive apparatus (Hemmingsen, 1950).6. The actual weight of stomach contents, and the wet and lipid weights of the hepatopancreas (level or b) are not fixed and reflect relative energetic demands or availability.7. During the stages undergoing regular molts (immature and prepubescent) these variables exhibit high level implying the maximal use of physiological capacity.8. At the stage of maturity, these levels decrease relative to the growing stages, implying the underutilization of this capacity.