Summary Three English barnacles were successfully reared in cultures showing a marked plant growth. Each of the three species has six naupliar stages and a cypris stage. Tables give the sizes and the setation of the appendages of all six naupliar stages of all three species. Notes on the discrimination of the nauplii of the three species are followed by a discussion of the general features of development, and reference is made to the eight naupliar stages found in Balanus crmalus by Herz (1933).

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SUMMARY. An African meliponid bee (Trigona (Hypotrigona) gribodoi Magretti) has been kept in observation nests near Accra, Gold Coast. The nests had up to 750 bees, honey and pollen store cells of 8 mm. height and 6 mm. diameter and brood cells of 31/2 mm. height and 21/2 mm. diameter arranged in clusters. The nests had a trumpet‐shaped tubular entrance and another tube running in to the nest. The nesting cavity is sealed where necessary by a thick propolis screen and the nest area may be cut off from the rest of the cavity by a wax sheet. The queen is physogastric. Drones take thirty‐two days from egg laying to emergence, are reared in cells identical with those of the worker caste and perform no work. Workers take thirty‐five days to develop and after emergence pass through five recognizable stages of increasing pigmentation. In the absence of a queen, workers lay eggs but only drones are reared. The five stages of the worker caste perform work on a rotation system comparable with that of the honey bee. Stage 1 performs no work: stage 2 rears the brood and feeds all castes; stage 3 ripens nectar and cleans the nest: stage 4 ventilates the nest and carries debris out; stage 5 guards the entrance and forages for nectar, pollen and propolis. A detailed description is given of activities in the nest. Foraging takes place mainly in the morning. There is a heavy brood mortality.