STOMACH CONTENTS AND MICROFEEDING OF SOME COMMON CIRRIPEDES

An account is given of the stomach contents of some common barnacles; these include both intertidal and sublittoral species. The contents reflect to some extent the environment, species taken from the same place at the same time having similar contents. With some species, a particle size analysis was possible on a pooled sample of stomach contents. It is evident that much debris is present, and that particulate matter with a diameter less than 2 μ can be taken. Detritus may be an important source of nutriment with sublittoral species. Small particles cannot be taken by the captorial activity of the cirri. It is considered that glandular secretions at the base of the cirri, where there are numerous setae, enmesh the food, which is then carried forward to the mouth parts to be rejected or accepted.

THE NAUPLIAR STAGES OF BALANUS HESPERIUS PILSBRY

The details of morphology of the six naupliar stages of Balanus hesperius are described, the material being referable to the forma laevidomus of Pilsbry. The nauplii are particularly characterized by a long and somewhat slender body and rather stiff appendages, the rami of which are thickened proximally. The general pattern of development conforms to that of other nauplii and is remarkably similar in all balanids. Tables of sizes and setation are given.

THE NAUPLIAR STAGES OF BALANUS NUBILIS DARWIN

The details of morphology of the six naupliar stages of Balanus nubilis are described. The nauplii are particularly characterized by their large size and in the later stages by a distinctly pentagonal outline. The general pattern of development conforms to that previously found for balanid nauplii. Tables are given of sizes and setation formulae.

On Anthony Askew, M.D., F.R.S., and his Library

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On Roman Medicine and Roman Medical Inscriptions found in Britain

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