* We are grateful to Dr. Mary D. Rogick for much of the information on which this and succeeding sections concerning bryozoan development are based.

The colonies of this form are tan or grey in color, and are composed of numerous pin-like individuals crowded together; the colonies are approximately one-half inch in height, and from one-half to one inch in extent. They are often found in association with Venus shells which are encrusted with the sponge, Cliona (Rogick, 1948), and are obtained by dredging in the Hole at Woods Hole, Mass. Barentsia is very similar to Pedicellina, but is larger, hardier, and easier to find.

Rogick ( 1948) reports that free-swimming larvae and embryos in various stages of development were obtained between July and September, but that very probably they are also obtainable earlier and later during the summer. It is not certain whether Barentsia is sometimes hermaphroditic (Rogick, 1948), but in many instances, at least, the sexes are separate.

A. Care of Adults: The animals are hardy and easy to keep in the laboratory if they are supplied with running sea water. They do not require feeding.

B. Procuring Embryos: Embryos and larvae are found within the calyx of the adult; larvae are released through a channel opening into the atrial cavity in front of the anal opening (Rogick, 1948).

The development of this form is apparently very much like that of Pedicellina (Rogick, personal communication), except that the embryos, larvae and adults are easier to study. Calyx regeneration is a conspicuous phenomenon in Barentsia and one which, as Rogick points out, is probably worthy of detailed study.

OSBURN, R. C., 1910. The Bryozoa of the Woods Hole region. Bull. U. 5. Burl Fisheries, 30:205-266.

ROGICK, M. D., 1948. Studies on marine bryozoa. II. Barentsia laxa Kirkpatrick 1890. Biol. Bull., 94: 128-142. (See, also, references for Pedicellina.)