The development of phyllosomas of the European spiny lobsterPalinurus elephas was examined in recirculating culture systems. Approximately 2000 newly hatched phyllosomas were introduced into each of three 100-L circular culture containers. Two of the containers, A and B, shared a filter; container C had a separate system of similar design. Hatched larvae of the sailfin sandfish Arctoscopus japonicus were fed to phyllosomas in container A, and pieces of the gonad of the mussel Mytilus edulis to those in container B. Phyllosomas in container C received both foods for the first 24 days; thereafter A. japonicus comprised their sole diet. Water temperature was maintained at 19–20˚C in containers A and B and at 16–18˚C in container C. Two individuals from container A and 10 from container C metamorphosed into pueruli after six instars at 65 and 69 days respectively, whereas earlier trials involved an estimated nine instars to metamorphosis after 132 days. Larvae thus cultivated were used to describe, for the first time, the morphological development of Palinurus elephas phyllosomas through metamorphosis to the puerulus stage. Fish larvae, such as A. japonicus may be an important dietary component for cultivation of palinurid phyllosomas.

SUMMARYA review is given of some mathematical programming methods suitable for optimization of structures needing matrix methods for analysis, An application is presented for elastic flat grillages made of straight orthogonal beams normally loaded. Empirical relationships are used to relate beam section properties so that each beam element has only one design variable. Optimization results are obtained by methods of stress-ratio, linear programmingmtting plane and usablefeasible gradient directions. A comparison of the efficiency of these methods is given for the grillage designs which are shown to have non-convex stress constraints and numerous relative optima. Instances are given of non-fully stressed global optima and fully stressed designs which are not local optima for cases with only stress constraints. Discussions include locating the global optima for grillage designs and extensions of the methods presented to other structural design problems.

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Histological incontinence of pigment (HIP) was studied using light and electron microscopy in a pigmented lesion from a female facial melanosis (FFM) patient and in another lesion produced by isoeugenol when the patient was patch tested. The following sequence of events is thought to underlie HIP. Phagocytes invade the epidermis and phagocytize melanosomes either in keratinocytes or in cytoid bodies, which are degenerated keratinocytes. These phagocytes then return to the dermis through gaps in the basal lamina.In brown guinea pigs sensitized to DNCB, 0.02% DNCB in acetone was applied repeatedly to the same area of the abdomen once per week for six weeks. HIP was observed in 28% of the animals following the fifth application of DNCB. In contrast to the HIP process observed in the patient, phagocytes in brown guinea pigs phagocytized free melanosomes. In irritant reactions to DNCB in brown guinea pigs, only concentrations which produced epidermal necrosis induced HIP.